Strategies for Road Project Execution with Land Access Restrictions: A Systematic Review

Abstract

Over the past decade the industry has developed technical, contractual and managerial tools for road construction without recognizing their capacity as solutions to land access restrictions. This systematic review analyzes the strategies for executing road projects under such restrictions. Following the PRISMA 2020 protocol, 51 indexed articles (2015–2026) retrieved from Scopus and Web of Science were examined and classified into land access restrictions, execution strategies (four families: technical–constructive, project management, social–institutional and contractual–legal) and impact on performance. Strategies are documented in 64.7% of the studies, but only 25.5% analyze them as an object, which explains why they have not been recognized as available solutions. The four families are not alternatives: they operate at different moments of the cycle, and their effectiveness depends on the type of restriction, the moment of activation and the institutional capacity, a determining variable that the corpus does not measure. Treating the restriction as a planning variable, rather than a contingency, distinguishes the projects with positive impact.

1. Introduction

By 2040, USD 94 trillion will be allocated to infrastructure by developing-country governments and multilateral organizations, representing a USD 15 trillion gap between projected and required investment, of which USD 8 trillion corresponds to road investment [1]. A significant share of those projects will be stalled, not for lack of resources, but because they face the specific condition of overcoming the impossibility of physically accessing the land on which they must be executed [2,3]. That condition has been addressed in the literature [4,5].

The specialized academic literature offers fragmented evidence on technical and constructive responses, project management instruments, social and institutional strategies and contractual and legal mechanisms [2,4,6,7,8]. This fragmentation has a root: the responses were never constituted as an object of study, so the field documents the restriction and records the strategies as a by-product, with no common object around which to articulate an integrated framework.

Within this fragmentation, some studies analyze the regulatory certainty of the acquisition process [9,10,11], others compare the distribution of risks under concession schemes [9,10] and others quantify the impact on schedule and cost [11,12].

The core theme has evolved through three stages of scientific contribution: until 2018, documentation of the land-related constraint predominated [2,13]; between 2019 and 2022, predictive quantitative models of impact emerged [4,14]; from 2023 onwards, social and contractual strategies gained academic prominence [15,16]. Despite emblematic cases and active concession programs in Peru, Colombia, Brazil and Mexico, Latin America has scarce representation in the scientific output on road execution strategies [17,18].

The available literature presents limitations on three planes. Thematically, the evidence offers no framework that comparatively evaluates the response families or the conditions that determine their effectiveness [19,20]. Methodologically, quantitative models and qualitative studies are produced along disjointed lines, with no frameworks that combine both approaches [15,21]. Geographically, the indexed literature on strategies applicable to civil-law jurisdictions with ejido land and indigenous communities is scarce [22].

The general objective is to analyze and evaluate the execution strategies for road projects facing land access restrictions during the period 2015–2026, identifying their impact on schedule, cost and scope. The specific objectives are: (1) to identify the documented land access restrictions according to their type and institutional context, as the condition that determines the applicability of each strategy family; (2) to evaluate the execution strategies identified according to their type, application conditions and reported effectiveness; and (3) to examine the reported impact on performance: schedule, cost, and scope. The selected articles comprise publications in journals indexed in Scopus and Web of Science concerning road infrastructure projects with explicit land access restrictions, selected through inclusion and exclusion criteria in accordance with the PRISMA 2020 protocol [23].

This review contributes three elements: a common analytical framework that classifies restrictions, strategies and impact and distinguishes the object of each study; the evidence that strategies are documented in most of the corpus but studied as an object in only a quarter of it; and the identification of the least developed space, the social and technical strategies that are recorded without being analyzed as a solution. The analysis draws on project risk management and treats the strategies as foreseen flexibility options of conditional effectiveness.

2. Materials and Methods

2.1. Systematic Review Design and PRISMA Protocol

The research was conducted as a systematic literature review with the objective of analyzing and evaluating the indexed evidence on strategies for the implementation of road projects with property limitations, considering publications from the period 2015–2026. The review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) [23], the international standard for evidence synthesis. The flow diagram is included (Section 2.4) to ensure continuous traceability throughout the entire selection process. The review protocol was not registered in a public repository prior to the implementation of the study.

This review distinguishes three concepts. The land access restriction is the condition that prevents full physical availability of the land required for execution, whether through pending acquisition, occupation, compensation conflict or release in sections. The execution strategy is the technical, managerial, social or contractual response deployed to advance the works under that restriction. Right-of-way management is the practice of securing and administering the corridor throughout the project cycle, articulating the restriction with the strategies. The analysis is grounded in the project risk management present in the corpus: Grubisic [12] applies a risk breakdown structure from the feasibility stage, and Demetracopoulou [6] assesses and allocates risk in design–build projects; on that basis, the strategies are interpreted as foreseen flexibility options whose effectiveness depends on the type of restriction, the moment of activation and the institutional condition.

2.2. Databases and Search Strategy

Scopus and Web of Science [24,25] were selected for their complementary coverage in engineering, social sciences and project management. The search was defined in English, Spanish and Portuguese for their complementary coverage of the phenomenon: English gathers the international production, including that of Asia and Africa, which is indexed in that language; Spanish incorporates Latin America, where road and transport gaps are a development demand; and Portuguese covers Brazil. The strings were built from the key concepts of land access restriction, road infrastructure and response strategies, and were executed in both databases on 11 March 2026; they appear complete and dated in Appendix A. The strategy was adapted to each platform: in Scopus over the TITLE-ABS-KEY field with LIMIT-TO operators for language, open access, source type, publication stage, document type and subject area; in Web of Science over the Topic field with its Research Areas. Web of Science returned records only in English and Portuguese and from 2016 onward, whereas Scopus additionally provided Spanish and the single 2015 study of the corpus [12]. The resulting geographical distribution confirms that language did not constrain coverage.

The records from both databases were integrated and deduplicated by matching title, author, year and DOI.

2.3. Inclusion and Exclusion Criteria

Without applying search filters, 3313 records were retrieved in total: 2849 from Scopus and 464 from Web of Science. The open access filter (FB7) was applied to guarantee full-text access to each study, a necessary condition for exhaustive extraction, verification of the eligibility criteria and reproducibility of the synthesis; in a review centered on developing economies, open access also favors the capture of Global South and diamond open access journals, and the resulting corpus maintained high quality. To refine article suitability, seven search filters (FB1–FB7) were applied, as described in

Table 1. Search filters applied in Scopus and Web of Science.

FB(n)	Filter	Inclusion	Exclusion
FB1	Publication Period	2015–2026	Before 2015 and after March 2026
FB2	Publication Period	Final publication	Preprints, in-press articles and Early Access
FB3	Document Type	Scientific articles (Article) and review articles (Review Article)	Conference proceedings, book chapters, editorials, letters and notes
FB4	Source type	Indexed journals (Journal)	Conferences, book series and technical reports
FB5	Subject area	Engineering, Social Sciences, Environmental Sciences, Business, Public Administration, Construction, Operations Management, Urban Planning, Architecture and Law	Medicine, Biology, Chemistry, Physics, Mathematics and areas unrelated to the object of study
FB6	Language	English, Spanish and Portuguese	Any other language
FB7	Open access	All Open Access	Restricted or paywalled articles

.

Four predefined eligibility conditions (EL1–EL4) were also defined, as described in

Table 2. Eligibility criteria for study screening.

Criterion	Description	Inclusion	Exclusion
EL1	Project type	Major road infrastructure construction projects in the pre-operational phase: roads, highways, tunnels, bridges or railways, with original empirical evidence and sufficient methodological detail	Routine maintenance, operation of existing roads, non-road infrastructure (buildings, industrial facilities, mining) and purely theoretical studies without original data
EL2	Land access restriction	Articles that explicitly document conditions of partial or restricted access to the land linked to road execution: acquisition delays, disputes with owners, unauthorized occupation, compensation conflicts or phased release of the worksite	Articles that mention land acquisition tangentially without reporting its effect on road project execution
EL3	Response strategy	Articles describing at least one constructive, project management, contractual, legal, regulatory or technological strategy applied or proposed as a response to land access restriction in road works	Articles that only document the land-related problem without describing any response strategy, action or solution
EL4	Empirical evidence	Articles that report the quantitative or qualitative impact of land access restrictions or applied strategies on project performance in schedule, cost or scope	Articles without reported performance indicators and narrative reviews without original data

, which operate cumulatively on the records that passed the previous filters, to ensure that each study incorporated into the corpus provided verifiable evidence directly linked to the object of the review.

2.4. Study Selection Process

The complete selection process is shown in Figure 1, following the PRISMA 2020 flow diagram [23]. After applying filters FB1–FB7, which excluded 2677 records, 636 records were obtained; duplicate removal reduced this volume by 77, leaving 559 records available for screening.

Screening of titles and abstracts of the 559 records, contrasted with conditions EL1–EL4 (Table 2), resulted in the exclusion of 503 records: 405 for not corresponding to road infrastructure (EL1), 97 for absence of land access restriction linked to execution (EL2), and 1 for lacking a documented strategy (EL3). The remaining 56 records advanced to full-text review.

The 56 articles that advanced were read in full, evaluating each against the four eligibility conditions with greater rigor than in the previous stage. Since all were available in open access, retrieval was complete. Five articles did not pass this evaluation: 3 addressed informal urban or mining infrastructure and did not meet EL1; 1 documented compensation outside the road scope and did not satisfy EL2; and 1 was a narrative review without original empirical evidence, which excluded it by EL4. Applying the same criteria in both stages ensured that each decision was traceable and reproducible. The final corpus comprised 51 articles. Details of the data processing and additional methodological information are provided in the Supplementary Materials.

2.5. Reliability of Selection and Study Screening

In the screening process, selection reliability was assessed through the independent review of the 559 records by two reviewers, who applied the eligibility criteria defined in Table 2; the results of this pre-consensus agreement are shown in

Table 3. Inter-reviewer agreement matrix for study selection prior to consensus.

	Reviewer 2: Include	Reviewer 2: Exclude	Total
Reviewer 1: Include	A = 46	B = 16	62
Reviewer 1: Exclude	C = 13	D = 484	497
Total	59	500	559

. Both reviewers agreed on 530 cases: 46 records included by both (cell A) and 484 excluded by both (cell D), reflecting a high level of initial agreement. Discrepancies arose in 29 cases: Reviewer 1 included records that Reviewer 2 excluded (B = 16), and Reviewer 1 excluded records that Reviewer 2 included (C = 13). These cases were discussed and resolved by consensus, ensuring coherence in the final eligibility decisions. Cohen’s Kappa coefficient (κ = 0.74) indicates substantial agreement [26]. This result supports the robustness and reproducibility of the selection process applied in this systematic review.

2.6. Bibliometric Methodologys

For the bibliometric analysis, VOSviewer 1.6.20 [27] was used with the metadata of the 51 articles exported from Scopus and Web of Science. A keyword co-occurrence network was built based on frequency and link-strength metrics, with a minimum threshold of 1 occurrence and normalization of terminological variants via an equivalence file. This analysis identified thematic clusters, links between research lines and areas with scarce coverage in the field.

2.7. Thematic Categorization

This systematic review organized the information extracted from the corpus by applying the qualitative categorization technique [28], whose purpose is to isolate the concepts of the phenomenon in order to study them with precision. Three categories and ten subcategories were defined (

Table 4. Thematic categorization of the corpus.

Category	Definition	Subcategory	Definition
C1. Land access restrictions	Type of land access restriction that conditions physical access to the site and determines the applicable strategy family.	C1.1 Land acquisition and expropriation	Documents the conflicts that arise during the formal land acquisition process: disputes over price, ownership or owners’ refusal to relinquish the property.
		C1.2 Social, cultural and informal conflicts	Records situations where communities, informal occupants or groups with cultural ties to the territory prevent or hinder access to the worksite.
		C1.3 Regulatory and institutional framework	Analyzes how land laws, decrees and public policies condition the land acquisition processes in road infrastructure projects.
C2. Execution strategies	Strategy, solution or mechanism documented for executing road projects under land access restrictions.	C2.1 Technical and constructive strategies	Documents how worksite teams adapt the design or reorganize construction to advance in available zones without waiting for full land release.
		C2.2 Project management strategies	Explores tools and methods to anticipate land-related delays, manage risks and recover the schedule when the land is not available.
		C2.3 Social and institutional strategies	Documents how negotiation, community consultation and inter-institutional coordination managed to unblock land access in road works.
		C2.4 Contractual and legal mechanisms	Analyzes how PPP and BOT contracts and extension-of-time clauses distribute the land-related risk between the State and the executors of road works.
C3. Impact on performance	Effect of the applied strategies on the performance of the road project under land access restrictions.	C3.1 Impact on schedule	Studies that document the effect on the schedule as the prioritized dimension.
		C3.2 Impact on cost	Studies that document the effect on the budget as the prioritized dimension.
		C3.3 Impact on scope	Studies that document the effect on the project scope as the prioritized dimension.

Note. PPP: public–private partnership; BOT: Build–Operate–Transfer.

): C1. Land access restrictions; C2. Execution strategies; and C3. Impact on performance. Each category is composed of subcategories, which are its elements. Each study was also classified by its object of analysis, the restriction (OR), the strategy (OE) or both (OER), to identify what each study examines. Two reviewers coded independently and resolved discrepancies by consensus, with the procedure validated in the screening (Cohen’s kappa = 0.74). Consistency was ensured by the predefined framework, double coding and consensus. The coding was recorded in an analytical matrix and references were managed in Zotero.

2.8. Quality Assessment of Included Studies

Methodological quality was assessed with the Mixed Methods Appraisal Tool (MMAT, 2018 version) [29], chosen because the corpus combines qualitative, quantitative and mixed designs under a single validated instrument. Two reviewers applied the two screening questions and the five criteria of each design to the 48 empirical studies, rating each criterion as Yes, No or Cannot tell, with justification verified against the full text; discrepancies were resolved by consensus. In accordance with the MMAT manual, no single overall score was computed and no study was excluded on quality grounds. The two systematic reviews were appraised with AMSTAR-2 [30], and the conceptual article [12] was described as such. The complete appraisal appears in

Table A1. Methodological quality appraisal of the included studies (MMAT 2018).

Study (Year)	MMAT Category	T1	T2	1	2	3	4	5	Verified Justification
Kazda et al. (2020) [32]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Methodology section explicitly applies historical monographic and typological methods (with methodological citation) to two airport expropriation cases; findings derive from the documented case chronologies
Babalola (2025) [22]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Self-declared qualitative design; interviews with affected residents and planning practitioners plus media content
Hasan Afandi and Basrun Umanailo (2018) [33]	1 Qualitative	Y	Y	Y	CT	Y	Y	Y	Qualitative case study in Watudakon village; primary data direct from community plus secondary legal documents; findings anchored in field responses and quoted officials (Regent statement village secretary interview); collection technique not specified
Aalders et al. (2021) [34]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Walking ethnography along LAPSSET corridor 2016–2019 with about 30 semi-structured in-depth interviews
Brock (2024) [18]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Political-ecology case study with fieldwork on the Lyon-Turin railway
Hofmann (2020) [35]	1 Qualitative	Y	Y	Y	CT	Y	Y	Y	Theoretically informed short article (Bull. Lat. Am. Res. 2020 39 S1 47–51) framed by developmentalist-discourse and neoliberal-rationality concepts in the author voice; findings traceably derived from cited official documents (23 April 2020 decree canceled SEMARNAT consultation) and recorded statements; data collection procedure not described
Pinuji et al. (2023) [20]	1 Qualitative	Y	Y	Y	Y	CT	Y	Y	Primary data from field observations and interviews; analysis procedure not detailed
Uribe (2019) [36]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Ethnographic account of road building and land legibility in the Colombian Amazon
Tassadiq (2024) [37]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Fifteen months of ethnography in Lahore: participant observation oral histories and interviews
Demetracopoulou et al. (2024) [6]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Twenty interviews with TxDOT and private-sector experts; inductive and axial coding declared
Danial et al. (2022) [2]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Qualitative identification of delayed site-possession causes from 15 project case studies with two-stage analysis
Zou et al. (2025) [7]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Interviews with 201 Zhuang minority residents plus participant observation and on-site interviews with cadres
Sari et al. (2022) [19]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Socio-legal method explicitly framed (Wheeler and Thomas); primary data from field identification and measurements plus Land Office secondary data; findings derived from statute analysis applied to the Semarang-Demak case
Buditiawan et al. (2022) [47]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Self-declared descriptive qualitative; documentation observation and in-depth interviews analyzed via Social Impact Analysis
Cupers (2025) [48]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Three months of fieldwork; 30 semi-structured and life-story interviews; archival research at Kenya National Archives
Indah et al. (2023) [49]	1 Qualitative	Y	Y	Y	Y	Y	CT	Y	Qualitative-explorative design; topic via biblioshiny; data from observation website documents and literature; analysis with NVivo 12 Pro and Vensim PLE explicitly declared; interpretation trail not fully detailed
Kahangirwe and Vanclay (2024) [50]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Analysis of 10 Ugandan road projects; document analysis in-depth and group interviews and field visits
Mohamed Azmi et al. (2025) [51]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Doctrinal examination of legislative resources and valuation methods (comparison cost investment residual profit) with confirmatory interviews at Sarawak Land and Survey Department; findings derived from legal sources and court practice
van der Ploeg and Vanclay (2018) [55]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Five months of ethnographic fieldwork plus document analysis of internal company documents
Ogwang and Vanclay (2021) [58]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Multi-method case study: document analysis of field observations, key informant interviews and focus groups
Bathla (2024) [61]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Critical ethnography along Delhi expressway 2018–2020 triangulated with local media reports
Nhat et al. (2025) [8]	1 Qualitative	Y	Y	Y	Y	Y	Y	Y	Semi-structured interviews with 57 participants and thematic analysis; design self-described as mixed-method qualitative (multiple qualitative techniques)
Mulyani et al. (2025) [16]	1 Qualitative	Y	Y	Y	Y	Y	Y	N	Stakeholder informants via snowball; Strauss–Corbin analysis from fieldwork onset with field notes of description and reflection; findings anchored in documented cases and Law 2/2012 provisions; methods section contradictorily self-describes as quantitative descriptive
Andrić et al. (2025) [39]	3 Quant non-randomized	Y	Y	Y	Y	Y	Y	Y	Dataset of 138 completed South Asian projects drawn from official ADB project completion reports (defined institutional frame); NVivo content analysis of delay causes plus regression functions and Random Forest modeling
Titirla et al. (2021) [21]	3 Quant non-randomized	Y	Y	Y	Y	Y	Y	Y	Delay data from 120 Greek projects in similar contractual environment; linear regression and neural network with 12 variables
Darsa et al. (2023) [45]	3 Quant non-randomized	Y	Y	Y	Y	Y	Y	Y	Three-phase design: 30 factors from literature and pilot; questionnaire to 340 with 245 responses (72.05 percent) and 10 excluded for incompleteness; ANN trained on 81 completed road projects administered by the Ethiopian Roads Administration each with an official schedule performance report (complete outcome data Table 8)
Leksono et al. (2019) [14]	3 Quant non-randomized	Y	Y	CT	Y	Y	Y	Y	UAV photogrammetry on the Cisumdawu corridor validated with 15 Ground Control Points and Independent Control Points and compared against conventional terrestrial measurement: single-site application limits representativeness
Hu and Han (2018) [53]	3 Quant non-randomized	Y	Y	CT	Y	Y	Y	Y	Value for Money assessment of the Heda freeway PPP case with sensitivity analysis across three scenarios (LAR responsibility discount rates profit margins); single-case representativeness not claimable
Shrivastava et al. (2019) [13]	4 Quant descriptive	Y	Y	Y	Y	Y	CT	Y	Samples and Instruments section: Defined target population (professionals in Indian railway projects); 520 responses received via email SurveyMonkey and hardcopy; sample adequacy formally tested (KMO 0.934 communality); EFA-PCA in SPSS (Statistics 26 (IBM Corp., Armonk, NY, USA); distributed count and response rate not reported
Devi (2025) [38]	4 Quant descriptive	Y	Y	Y	Y	Y	CT	Y	Survey of 72 professionals with reported composition (41.33 percent clients, 38.90 percent consultants, 12.50 percent contractors) plus preliminary data from 50 road projects; RII; response rate not reported
Kapote et al. (2023) [40]	4 Quant descriptive	Y	Y	Y	CT	Y	Y	Y	Questionnaire plus field visits across 25 Maharashtra road and highway projects from PWD ZP municipal corporation contractors and consultancies; all 25 instruments completed by experienced field professionals and objective performance measures computed from project records; selection method of the 25 projects not described
Nguekam et al. (2019) [42]	4 Quant descriptive	Y	Y	Y	Y	Y	Y	Y	Satellite identification field campaign and GIS processing producing full census of 1502 impacted buildings (census design eliminates non-response risk)
Sandhyavitri et al. (2017) [44]	4 Quant descriptive	Y	Y	Y	Y	Y	CT	Y	Survey covering the national toll regulator (BPJT) and the four major toll operators by name: near-census of the relevant institutional population; probability–impact scores processed with Monte Carlo and tornado; non-response not discussed
Zhang et al. (2025) [46]	4 Quant descriptive	Y	Y	Y	Y	Y	CT	Y	Expert-scoring survey of 168 senior engineers across institutions (April 2025) with AHP entropy weighting and consistency tests
Gatitu et al. (2021) [15]	4 Quant descriptive	Y	Y	Y	Y	Y	Y	Y	Self-declared cross-sectional descriptive survey; defined target population (clients, consultants, contractors) sample of 80 with reported stakeholder distribution and 87.5 percent response rate; RII analysis
Karimi et al. (2022) [56]	4 Quant descriptive	Y	Y	Y	Y	Y	Y	Y	Questionnaire distributed to 100 participants with 79 valid responses (79 percent response rate); RII and Spearman analysis
Nikjow et al. (2021) [3]	4 Quant descriptive	Y	Y	Y	Y	Y	Y	Y	Questionnaires distributed to 115 respondents with 106 credible responses (92 percent response rate); respondent background (experience roles) reported in Figure 2; RII plus Shapiro–Wilk checks
Ting Sim Nee et al. (2022) [57]	4 Quant descriptive	Y	Y	Y	Y	Y	Y	Y	Occurrence and impact analysis from project files and correspondence of 111 Sarawak public projects (records-based no non-response)
Idrees et al. (2021) [59]	4 Quant descriptive	Y	Y	Y	Y	Y	CT	Y	Random sampling with formal sample-size formula (Tanis and Hogg) requiring n = 84; 78 valid responses obtained near target; stakeholder groups represented; Cronbach alpha reliability; distributed-to-received ratio not reported
Nguyen P.T. (2025) [54]	4 Quant descriptive	Y	Y	Y	Y	Y	CT	Y	Survey of 90 PPP experts all with substantial documented experience and written rating guidelines; FACULTY (consequence–likelihood plus spherical fuzzy AHP); non-response not reported
Huynh et al. (2026) [5]	5 Mixed methods	Y	Y	Y	Y	Y	Y	Y	Sequential mixed-methods design; statistical analysis explicitly explored consensus and divergence among stakeholder groups and project sizes producing an integrated account of convergence partial alignment and divergence
Li et al. (2021) [41]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	Staged hybrid design with explicit rationale: Conceptual model then 10 expert semi-structured interviews (6 practitioners, 4 scholars, over 8 years experience) refining the questionnaire then fuzzy set screening; divergence handling not reported
Putri et al. (2024) [43]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	Self-declared sequential exploratory mixed method combining qualitative and quantitative phases
Putri et al. (2023) [52]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	Self-declared concurrent triangulation; stakeholder interviews plus questionnaires to 325 affected residents with equal weighting
Takano (2018) [17]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	A total of 201 structured surveys to randomly selected household heads (48.2 percent of universe, 95 percent CI, 5 percent error) with current and retrospective data integrated with qualitative methods on the same case; divergence handling not reported
Nguyen et al. (2020) [10]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	In-depth interviews with six PPP experts informing questionnaire survey of 150 respondents analyzed with word cloud technique
Samoilov et al. (2024) [9]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	Explicitly justified mixed design (qualitative depth of PPP markets plus statistical breadth of 261-respondent survey) documented in six methodological stages with systematic country selection; divergence handling not reported
Rabe et al. (2020) [60]	5 Mixed methods	Y	Y	Y	Y	Y	CT	Y	Two-step design: descriptive statistics of 153 Chinese infrastructure cases (weighted average cost overruns) plus two in-depth case studies
Saeedi et al. (2019) [4]	NA Review	NA	NA	NA	NA	NA	NA	NA	Review article (3 databases, explicit keywords, 1985–2018, flowchart, 43 papers accounted justified approach with declared limitations); single-pass abstract screening no a priori protocol no duplicate selection no appraisal of its 43 included studies (confirmed at fourth reading: rigor mentions in text describe the reviewed studies not its own method); AMSTAR-2
Zhasmukhambetova et al. (2025) [11]	NA Review	NA	NA	NA	NA	NA	NA	NA	PRISMA-guided systematic review of 83 studies implemented in EPPI-Reviewer with a priori protocol independent reconciled screening and an MMAT quality appraisal of its included studies; appraised with AMSTAR-2
Grubisic et al. (2015) [12]	NA Conceptual	NA	NA	NA	NA	NA	NA	NA	Conceptual framework paper: risk categories and investigative questions proposed and illustrated on the Brazil HST case using secondary sources (IPEA feasibility studies); the authors themselves state the model needs future testing in practice to validate the categorization and evaluate the proposed risks; no primary data collection hence outside the scope of empirical appraisal tools

T1–T2: screening questions; 1–5: criteria of the MMAT category. Y = yes; NA = not applicable; CT = cannot tell. Two reviewers; consensus. No overall score is computed and no study is excluded (MMAT 2018 manual).

and

Table A2. Critical appraisal of the two included systematic reviews (AMSTAR-2).

AMSTAR-2 Item	Saeedi [4]	Zhasmukhambetova [11]	Evidence
1. Research question and inclusion criteria include the components	Y	Y	Defined scope and eligibility components
2. Protocol established prior to the review	N	PY	[11]: Detailed a priori protocol published as its Supplementary Material; registration not stated. [4]: No protocol mentioned
3. Selection of study designs explained	N	Y	Ref. [11] justifies empirical-focus eligibility; Ref. [4] does not discuss design selection
4. Comprehensive literature search strategy	PY	Y	[4]: Three databases (IEEE Xplore Scopus Google Scholar), keywords and 1985–2018 window with flowchart. [11]: Databases, search engines, organization websites, physical books; full terms in S1; EPPI-Reviewer
5. Study selection performed in duplicate	N	Y	[11]: Screening conducted independently and reconciled; inconsistencies resolved through discussion. [4]: Not reported
6. Data extraction performed in duplicate	N	PY	[11]: Data extraction form in protocol S1; duplicate extraction implied by reconciliation. [4]: Not reported
7. List of excluded studies with justification	N	N	Neither provides an itemized excluded-studies list (PRISMA counts only in [11]: 1295 to 83)
8. Included studies described in adequate detail	Y	Y	[4]: Categories defined in detail. [11]: Detailed analysis of 83 studies
9. Risk of bias of included studies assessed	N	Y	[11]: MMAT Quality Appraisal Report published as its Supplementary Material. [4]: No appraisal
10. Funding sources of included studies reported	N	N	Standard gap in both
11. Appropriate methods for statistical combination	NA	NA	No meta-analysis conducted in either (narrative synthesis)
12. Risk of bias impact on meta-analysis assessed	NA	NA	No meta-analysis
13. Risk of bias accounted for in interpretation	Y	Y	Ref. [11] discusses quality in its Limitations chapter; Ref. [4] explicitly accounts for study weaknesses when interpreting (case-specific scope qualitative predominance and small samples reducing reliability) confirmed at final reading
14. Heterogeneity discussed and explained	Y	Y	Ref. [4] notes qualitative predominance and small samples of prior work; Ref. [11] has a dedicated Limitations section
15. Publication bias investigated	NA	NA	No quantitative synthesis
16. Conflicts of interest reported	Y	Y	Both declare no conflicts; Ref. [11] also declares funding (Bolashak scholarship)
Overall confidence (strict rule)	Critically low (critical flaws in items 2, 7, 9)	Moderate (single critical weakness: no excluded-studies list)	Per AMSTAR-2 rules: more than one critical-domain flaw lowers overall rating. Neither review is excluded from the corpus; appraisal informs interpretation weight

Y = yes; PY = partial yes; N = no; NA = not applicable (no meta-analysis).

in Appendix A.

3. Results

3.1. Characterization of the Corpus

Table 5. Geographical distribution of the corpus by continent, country, and database.

Continent	Country	Continent		Country		Scopus Only		Scopus + WoS
		n	%	n	%	n	%	n	%
Asia	Indonesia	32	63%	10	19.6%	8	15.7%	2	3.9%
	China			7	13.7%	6	11.8%	1	2.0%
	Vietnam			4	7.8%	3	5.9%	1	2.0%
	India			4	7.8%	3	5.9%	1	2.0%
	Malaysia			3	5.9%	3	5.9%	0	0.0%
	Pakistan			2	3.9%	2	3.9%	0	0.0%
	Kazakhstan			1	2.0%	1	2.0%	0	0.0%
	Afghanistan			1	2.0%	1	2.0%	0	0.0%
Africa	Kenya	7	14%	3	5.9%	3	5.9%	0	0.0%
	Uganda			2	3.9%	2	3.9%	0	0.0%
	Cameroon			1	2.0%	1	2.0%	0	0.0%
	Ethiopia			1	2.0%	0	0.0%	1	2.0%
Europe	United Kingdom	6	12%	2	3.9%	1	2.0%	1	2.0%
	Croatia			1	2.0%	1	2.0%	0	0.0%
	Germany			1	2.0%	0	0.0%	1	2.0%
	Greece			1	2.0%	1	2.0%	0	0.0%
	Netherlands			1	2.0%	1	2.0%	0	0.0%
Latin America	Peru	4	8%	1	2.0%	1	2.0%	0	0.0%
	Mexico			1	2.0%	1	2.0%	0	0.0%
	Colombia			1	2.0%	1	2.0%	0	0.0%
	Brazil			1	2.0%	1	2.0%	0	0.0%
North America	USA	2	4%	2	3.9%	1	2.0%	1	2.0%
Oceania		0	0	0	0	0	0	0	0
Total		51	100%			42	82.4%	9	17.6%

shows that the corpus is concentrated in the Global South: Asia (63%), Africa (14%) and Latin America (8%) gather more than 80% of the studies, against 16% for Europe and North America. The evidence therefore comes mostly from developing economies. The quality assessment supported the reliability of the synthesis: of the 48 empirical studies, 27 met all five MMAT criteria and 21 met four, with none below four, which reinforces confidence in the synthesized patterns without any single study determining them.

The cross-tabulation between methodological approach and categories shows that the problem and the responses are studied through different lenses. Land access restrictions (C1) are addressed predominantly qualitatively (seven of nine studies). Execution strategies (C2) mobilize the full methodological spectrum (12 qualitative, 11 quantitative, nine mixed), and impact (C3) combines qualitative and quantitative approaches. When the geographical distribution (Table 5) is considered, that diversity is uneven: Asia, the dominant region, concentrates the bulk of the quantitative and mixed studies, whereas Latin America is examined only through qualitative and mixed approaches, with no quantitative work.

Table 6. Methodological approach of the corpus by category and subcategory (n = 51).

Methodological Approach	No. of Articles	%
Qualitative	23	45.1%
Quantitative	16	31.4%
Mixed	10	19.6%
Systematic Review	2	3.9%
Total	51	100%

shows the consolidated methodological approaches of the corpus by category and subcategory of the eligible sample of the study.

Table 7. Bibliometric quality of the corpus by SJR quartile (n = 51).

SJR Quartile	No. of Articles	%
Q1	15	29.4%
Q2	16	31.4%
Q3	15	29.4%
Q4	4	7.8%
No assigned quartile (N/A)	1	2.0%
Total	51	100%

Note. Q1–Q4: Journal quartile according to SCImago Journal & Country Rank (SJR) at the year of publication. Q1 + Q2%: Percentage of articles published in first- or second-quartile journals.

, which classifies journals by their quartile in the SCImago Journal & Country Rank (SJR) [31], shows a solid quality base: 61% of the corpus was published in Q1 or Q2 journals and only 7.8% in Q4, a quality complemented by the study-level appraisal (MMAT, Section 2.8). Quality is unevenly distributed by object: studies that examine the strategy as an object are published in lower quartiles (mean Q2.75; only one in Q1) than those that study the restriction (mean Q1.94; eight in Q1). Qualitative studies occupy higher quartiles (mean Q1.57) than quantitative ones (mean Q2.69), so that Latin America, of qualitative profile, reaches the best mean quartile (Q1.75) and Asia, quantitative, the lowest (Q2.17).

Production accelerates and unites the recent literature: 47% of the corpus (24 of 51 studies) is published in 2023–2026, with a methodological shift from qualitative toward mixed designs. The object of study also evolves: between 2019 and 2022 studies centered predominantly on the restriction (10 of 21), whereas from 2023 those that jointly address restriction and strategy grow in number (12 of 24). Studies that treat the strategy as an explicit object remain scarce throughout the period. The field expands, but the strategy as an object does not consolidate (Figure 2).

3.2. Bibliometric Analysis

The co-occurrence network shows a dense core (project management, infrastructure, land acquisition) and disconnected peripheral clusters: agrarian law, ethnic cultures, and quality certification. That disconnection indicates that the field associates the restriction with planning and management but does not integrate the legal-agrarian frameworks, the cultural factors or the quality standards. The fragmentation of the network coincides with the still undeveloped solution space (Figure 3).

3.3. Thematic Synthesis

The thematic synthesis reveals an asymmetry between the content and the object of the corpus. Execution strategies (C2) appear in 64.7% of the studies, but only 25.5% (13 studies) analyze them as an explicit object; of these, eleven correspond to project management and contractual mechanisms, and nine come from the Asian context. Social strategies, despite being the second most documented family (10 studies), and technical ones are almost always studied alongside the restriction and only once as an object. The field examines management and contractual responses as an object and documents the social and technical ones as a by-product (

Table 8. Distribution of the corpus by category and subcategory (n = 51).

Category	Subcategory	No.	%
C1. Land access restrictions	C1.1 Land acquisition and expropriation	3	6%
	C1.2 Social and informal conflicts	2	4%
	C1.3 Regulatory and institutional framework	4	8%
C2. Execution strategies	C2.1 Technical and constructive strategies	5	10%
	C2.2 Project management strategies	13	25%
	C2.3 Social and institutional strategies	10	20%
	C2.4 Contractual and legal mechanisms	5	10%
C3. Impact on performance	C3.1 Impact on schedule	5	10%
	C3.2 Impact on cost	3	6%
	C3.3 Impact on scope	1	2%
Total		51	100%

).

Table 9. Thematic synthesis of the corpus (n = 51).

Author [No.] (Year)/Approach	Object	Main Finding	Contribution to Management
C1.1 Land acquisition and expropriation—C1. Land access restrictions
Kazda et al. [32] (2020), Qualitative	OR	Expropriation (eminent domain) of private property generates conflicts and prolonged bottlenecks in the courts.	Strategy: Imposition of expropriation as a last resort. Impact: Negative on schedule; it stalls physical execution by displacing the conflict to prolonged lawsuits.
Mulyani et al. [16] (2025), Mixed	OR	The lack of space to negotiate nullifies the agreement, forcing the government to deposit the money with the courts (consignment).	Strategy: Forced judicial consignment of compensation funds. Impact: Negative on schedule; the community rejects the money, blocking schedule progress.
Shrivastava et al. [13] (2019), Quantitative	OR	Land acquisition and site handover is a critical risk that causes cost and time deviations in Asian countries.	Strategy: Contractual classification of land unavailability as an external fundamental risk. Impact: Protects the contractor’s cost and schedule by exempting them from penalties for exogenous delays.
C1.2 Social, cultural and informal conflicts—C1. Land access restrictions
Babalola [22] (2025), Qualitative	OR	Ignoring informal occupants in expropriation provoked protests, marginalization and landlessness, materializing displacement risks.	Strategy: Mass forced eviction without census or prior mitigation. Impact: Total paralysis of the works due to physical resistance, destroying the project’s schedule.
Hasan Afandi and Basrun Umanailo [33] (2018), Qualitative	OR	The community rejected the compensation; the government used the courts and coercively demolished dwellings, generating social conflict.	Strategy: Physical demolition backed by courts after rejection of the fair price. Impact: Negative on schedule and cost; produced wooden blockades that stopped the machinery.
C1.3 Regulatory and institutional framework—C1. Land access restrictions
Aalders et al. [34] (2021), Qualitative	OR	There is a legal clash between community land rights and compulsory acquisition; excluded communities contest the works.	Community strategy: Pastoralist communities established settlements directly on the corridor alignment to force the renegotiation of their land rights. Impact: Alters the original scope and fragments the schedule.
Brock [18] (2024), Qualitative	OR	Railway projects use hybrid bills to grant automatic expropriation, bypassing planning laws.	Strategy: Use of parliamentary hybrid bills to bypass municipal audits. Impact: Secures the land quickly in schedule terms by concentrating expropriation authority in parliament, bypassing ordinary municipal controls.
Hofmann [35] (2020), Qualitative	OR	The State exploits crises to decree megaprojects as essential, privatizing ejidos and ignoring indigenous rights.	Strategy: Presidential decrees of national priority during health emergencies. Impact: Positive on schedule; accelerates physical occupation by suppressing community legal protections.
Pinuji et al. [20] (2023), Qualitative	OR	The law designates flooded areas as obliterated land, revoking tenure without compensation, which paralyzed the project.	Strategy: Regulatory shortcut to revoke rights over flooded areas while avoiding payments. Impact: Total failure; triggered judicial opposition that paralyzed the works for 5 years in schedule.
C2.1 Technical and constructive strategies—C2. Execution strategies
Uribe [36] (2019), Qualitative	OER	Requiring formal deeds from traditional occupants (legibility) aggravated the tenure conflict and paralyzed the works for 10 years.	Strategy: Imposition of formal cadastral mapping on informal lands. Impact: Generates prolonged paralysis in schedule and forces redesign of the alignment to bypass tenure conflicts, affecting scope and cost.
Tassadiq [37] (2024), Qualitative	OER	Colonial law excludes informal occupants; the State improvises extraordinary subsidies (grant-in-aid: exceptional payments outside the formal legal framework) to prevent the works from stopping.	Strategy: Creation of economic escape valves (off-legal payments) to settle informal occupants. Impact: Deactivates violent blockades, preventing lethal cost overruns in schedule.
Demetracopoulou et al. [6] (2024), Qualitative	OE	In design–build contracts, the contractor applies three strategies to address right-of-way restrictions: geometric alignment optimization to avoid conflicting parcels, alternative designs to bypass restrictive elements, and prioritization of available parcels in the construction sequence.	Allocating the land-related risk to the contractor in the design phase activates technical strategies that make it possible to reduce or eliminate conflicting parcels without waiting for formal resolution of the land, protecting the project’s schedule and scope.
Devi [38] (2025), Quantitative	OER	Delay in handing over the site to the contractor (influenced by the government) is a factor that directly impacts time.	Strategy: Application of RSI and PCA to rank delay factors and identify late site handover as the dominant client-side factor. Impact: Allows managers to focus mitigation on land release, reducing schedule deviations.
Danial et al. [2] (2022), Qualitative	OER	The contractor applied three physical strategies across three Malaysian road infrastructure projects: sectional site handover under Clause 38.3, allowing work to proceed in released sections while blocked areas remained inaccessible; alignment changes to bypass conflicting land; and formal scope downsizing as a last resort when other options failed to resolve the blockage.	Sectional site handover with progress in released sections (Clause 38.3) and alignment change are the constructive strategies that make it possible to maintain physical progress of the works while full land possession has not been completed.
C2.2 Project management strategies—C2. Execution strategies
Andrić et al. [39] (2025), Quantitative	OE	The Random Forest model outperforms linear regression in predicting delays across 138 South Asian megaprojects (F = 253.27 vs. 0.25), identifying land acquisition and resettlement as the main causes of delays averaging 86.66% of the baseline schedule.	The Random Forest model accurately calibrates the schedule floats required for land acquisition in South Asian projects, enabling realistic contractual schedules that absorb the land-release process.
Grubisic et al. [12] (2015), Qualitative	OE	Extra land acquisition is an explicit, categorical risk in high-speed train projects.	Strategy: Application of the risk breakdown structure (RBS) in the early phase. Impact: Isolates the risk and prevents cost overruns by injecting contingency budgets from the feasibility phase.
Huynh et al. [5] (2026), Mixed	OER	The digitization of cadastral files is the main factor reducing site-clearance time in Vietnamese road projects (F = 21.514, p < 0.001), especially in small projects lacking digital databases and large projects with high file volumes.	Administrative digitization of cadastral files and inter-institutional coordination reduce the right-of-way clearance time and protect the project’s critical path before construction starts.
Kapote et al. [40] (2023), Quantitative	OER	Road projects experience cost and time growth due to ineffective contractor pre-qualification mechanisms.	Strategy: Mathematical filter of bidders. Impact: Prevents cost and schedule escalations by ensuring that only contractors with solvency take on the project’s land access restrictions.
Leksono et al. [14] (2019), Quantitative	OE	The integration of UAVs, geodetic GPS, and photogrammetry enables cadastral mapping with a 0.128 m error in toll-road land acquisition zones, accelerating parcel certification and allowing construction to begin with only 35% of the land released.	The UAV reduces the cadastral certification time of untitled parcels and enables construction to start with partially released land, protecting the contractual start date of the road works.
Li et al. [41] (2021), Mixed	OER	Fuzzy set theory weighted by expert judgment identifies land acquisition and resettlement as the second most severe risk among 75 factors in Chinese infrastructure megaprojects, with an impact value of 3.510 and the highest severity among economic risks.	Prioritizing the land-related risk in second place out of 75 factors through fuzzy sets makes it possible to allocate specific budget contingencies before the start, protecting the project’s cost against acquisition uncertainty.
Nguekam et al. [42] (2019), Quantitative	OE	Map overlay in Geographic Information System (GIS) reveals exactly 1502 impacted buildings.	Strategy: Objective satellite survey using GIS tools (software version not applicable; GIS applied as a methodological approach). Impact: Adjusts and limits indemnities to their real value, protecting the cost baseline.
Putri et al. [43] (2024), Mixed	OER	The social risk index quantifies conflict probability on customary Ulayat lands before acquisition; on the Sicincin–Padang toll road, its prior use could have prevented delays exceeding two years caused by unidentified conflicts.	The anticipated assessment of land-related social risk through a quantified index makes it possible to identify the parcels with the greatest potential conflict and to design differentiated strategies of compensation and consultation before the works begin.
Saeedi et al. [4] (2019), SR	OE	A multiple regression model validated on 35 U.S. highway projects predicts right-of-way acquisition duration using parcel condemnation, parcel number, and design changes: duration = 142 + 738 × condemnation + 2.26 × parcels + 3.28 × revisions. The model supports realistic bidding dates and protects construction schedules from acquisition uncertainty.	Strategy: Application of predictive software and multiple regression equations. Impact: Allows setting realistic bidding dates, protecting the critical path against schedule deviations.
Sandhyavitri et al. [44] (2017), Quantitative	OE	Land acquisition cost is a high-uncertainty variable with severe impact on the final budget.	Strategy: Application of the Pareto Principle, Monte Carlo simulations and tornado diagrams. Impact: Statistically confines the damage from interest during construction (IDC), shielding cost.
Darsa et al. [45] (2023), Quantitative	OER	An artificial neural network using the Garson algorithm identifies late land acquisition as the fifth delay factor (6.54%) in Ethiopian road projects by foreign contractors, distinguishing it more accurately than the conventional Relative Importance Index.	The artificial neural network makes it possible to focus mitigation resources on the highest-impact land-related factors, guiding preventive management toward anticipated land acquisition as a lever to protect the schedule.
Titirla et al. [21] (2021), Quantitative	OE	A neural network with 12 input variables, including land requirements, predicts Greek highway duration with a mean squared error of 1.53 × 10−6, far outperforming two-variable linear regression.	Including land requirement as a predictive variable in the neural model substantially improves the estimation of actual duration, enabling contractual schedules that absorb the land process and reduce the risk of schedule overruns.
Zhang et al. [46] (2025), Quantitative	OE	The risk originating from delayed compensation payments obtains the highest severity score for construction.	Strategy: Use of the Improved Entropy Method combined with the Analytic Hierarchy Process (AHP). Impact: Isolates the real weight of the land-related contingency by eliminating biases, shielding cost.
C2.3 Social and institutional strategies—C2. Execution strategies
Zou et al. [7] (2025), Qualitative	OER	Political micro-mediation with Zhuang ethnic leaders unblocked access to the Sacred Rock on the G75 corridor in Guangxi (China), where the spiritual value of the site made any formal mechanism of monetary compensation or expropriation impossible.	Strategy: Political micro-mediation carried out by local leaders (village cadres). Impact: Positive on schedule and scope; pacifies the intra-family dispute without altering the road’s geometry.
Sari et al. [19] (2022), Qualitative	OER	The application of Indonesian Government Regulation No. 18/2021 enabled compensation for land destroyed by tidal flooding, unblocking land acquisition for the Semarang–Demak toll road and resolving the legal vacuum that had halted the works.	The application of the regulatory framework for land destroyed by climate events enables compensation and works progress in road corridors affected by flooding, resolving the legal blockage without requiring judicial resolution.
Buditiawan et al. [47] (2022), Qualitative	OER	The social impact study, combined with Minangkabau local wisdom and mediation by the Ninik Mamak, unblocked Ulayat land disputes in West Sumatra where formal mechanisms under Law 2/2012 had failed.	The social impact study integrated with local customary authorities is the strategy that unblocks Ulayat lands when formal legal instruments are insufficient; its effectiveness depends on activation before construction begins.
Cupers [48] (2025), Qualitative	OR	Pastoralist communities in Isiolo used the LAPSSET corridor as a catalyst for historical land claims, forcing the project to seek alternative locations for the resort city due to community opposition.	Institutional redress of historical land-titling debts is the precondition for unblocking corridors with second-generation restrictions; standard monetary compensation does not operate in these contexts of historical exclusion.
Indah et al. [49] (2023), Qualitative	OER	The concessionaires take on delegated roles (CSR) to commercially enable fragmented sections of the Trans-Sumatra toll road.	Strategy: Constructive sectionalization and delegation of social unblocking to operators. Impact: Maintains partial corridor functionality and investment returns through modular openings as land is released, avoiding total paralysis from customary land restrictions.
Kahangirwe and Vanclay [50] (2024), Qualitative	OER	Including resettlement costs in project financing from the design phase, under IFC (2023) standards, removes site-access blockages caused by unfunded compensation payments in ten Ugandan road projects.	The anticipated incorporation of the resettlement budget into project financing is the strategy that prevents site-access blockages due to delayed payments in road projects in Sub-Saharan Africa.
Mohamed Azmi et al. [51] (2025), Qualitative	OER	The government lacks regular procedures to compensate customary rights, requiring exceptional payments.	Strategy: Authorization of special ex gratia payments outside the formal norm for informal affected parties. Impact: Deactivates pockets of violence, preventing schedule extensions.
Putri et al. [52] (2023), Mixed	OE	Community exclusion from route selection and valuation generated friction; the pseudo-participatory consultative approach failed.	Strategy: Binding tripartite communicative planning policy (community–state–private). Impact: Participatively shields the geometric scope and speeds up schedule agreements.
Takano [17] (2018), Mixed	OER	Individual negotiations secured land for Lima’s Yellow Line at low cost, but harmed 74.6% of displaced residents, closed 47 of 70 home-based businesses, and fragmented family networks, exposing the social limits of resettlement as a land-release strategy.	Strategy: Door-to-door, individualized negotiation to divide communal resistance. Impact: Secures the physical road in scope and minimizes corporate cost, shifting financial ruin to the displaced.
Gatitu et al. [15] (2021), Quantitative	OER	Resolving land ownership disputes before tendering curbs the occurrence and mitigation of variation orders.	Strategy: Resolution of land disputes as a tender prerequisite (RII = 0.749). Impact: Reduces variation orders, protecting cost and schedule; in economies with high land informality, its application requires additional unblocking instruments because full possession before tendering is not always achievable.
C2.4 Contractual and legal mechanisms—C2. Execution strategies
Nhat et al. [8] (2025), Mixed	OER	Simplified land acquisition and participatory planning reduce land-related costs in PPP public transport projects, where site clearance can account for up to 80% of the total budget according to the World Bank.	Simplified land acquisition and continuous dialogue with communities reduce site-clearance costs and protect the financial viability of the contract under the PPP scheme in the face of the land barrier.
Hu and Han [53] (2018), Quantitative	OE	Land acquisition (LAR) is the main source of social instability that deters private capital.	Strategy: Legal assignment of LAR risk exclusively to the government. Impact: Generates positive Value for Money, protecting the firm’s cost and schedule under PPP schemes.
Nguyen et al. [10] (2020), Mixed	OE	Adequate and precise risk allocation (such as land) is the Critical Success Factor in PPP contracts.	Strategy: Structuring of guarantees through international consortia and multilateral institutions. Impact: Isolates the local risk, protecting commercial profitability and cost budgets.
Nguyen, P.T. [54] (2025), Mixed	OE	The FACULTY method identifies land acquisition and compensation as the most critical risk among 27 factors in Vietnamese concession-based infrastructure projects, quantifying its uncertainty more precisely than conventional methods.	Strategy: Dynamic adjustment clauses and automatic extension of the concession period. Impact: Absorbs delays by translating the financial impact into an increase in the operating schedule.
Samoilov et al. [9] (2024), Mixed	OER	Multidimensional flexibility models reduce losses from land acquisition delays in concession projects in Colombia, Kazakhstan, and Ghana. In Colombia, late land acquisition ranks among the top five risks, with an impact of 3.71.	Strategy: Implementation of multidimensional flexibility models and financial system dynamics. Impact: Cushions operational losses, recovering cost despite stalled parcels.
C3.1 Impact on schedule—C3. Impact on performance
van der Ploeg and Vanclay [55] (2018), Qualitative	OR	Execution in seven sections and parallel deployment of five resettlement firms over 600 km reduced land-related blockages and maintained corridor progress, though resettlement was delayed by up to three additional years.	Segmenting the corridor into independently executable sections makes it possible to protect the overall schedule when the land restriction is partial and localized.
Karimi et al. [56] (2022), Quantitative	OR	Spearman analysis (n = 79) identifies land acquisition as the main delay factor in Afghan road projects, with negotiations with tribal leaders and community sensitization programs used to protect schedules.	Quantifying the land-related impact on the schedule through RII and Spearman makes it possible to prioritize unblocking actions and negotiate contractual extensions with statistical evidence.
Nikjow et al. [3] (2021), Quantitative	OR	The EPC Fast-Track model starts construction before full land release; in the Mecca Light Railway, this led to a 34.4% cost overrun and major schedule delays due to the absence of land-flexibility clauses.	Including EOT clauses and contractual tolerance for partial land blockages in EPC contracts is the condition that protects the schedule when the land is not fully released at the start.
Ting Sim Nee et al. [57] (2022), Quantitative	OR	In 111 Sarawak projects, continuation from available chainage and physical relocation of works protected schedules despite lack of site possession, resulting in official EOTs instead of total stoppages.	Starting from the chainage (available metric chain along the alignment) and formalizing the EOT as a contractual instrument make it possible to maintain productivity and transfer the responsibility for the delay to the promoter, protecting the contractor’s schedule.
Zhasmukhambetova et al. [11] (2025), SR	OR	The synthesis of 83 global studies confirms that early ROW sequencing with specific schedule float assigned and deferred mobilization of blocked fronts are the highest-impact strategies documented to protect the schedule.	Allocating specific time contingencies for land acquisition from the planning phase is the preventive measure with the strongest empirical support for protecting the schedule in road projects.
C3.2 Impact on cost—C3. Impact on performance
Ogwang and Vanclay [58] (2021), Qualitative	OR	Separate state financing of land compensation (USD 40M of Uganda’s own funds) and advance acquisition without an approved loan are strategies that unblock the corridor and protect the cost of the main contract, although they transfer the sovereign cost to the host State.	Separating the land-compensation budget from the construction budget and advancing it as an enabling condition for the main contract protects the project’s cost structure vis-à-vis international creditors.
Idrees et al. [59] (2021), Quantitative	OR	Package-based execution (Metro Multan) and alignment modification with station relocation (Orange Line Lahore) are the documented strategies that allow continued physical progress and protect cost in the face of judicial land blockages (RII = 0.808).	Independent package-based execution and direct negotiation with market-price compensation are the responses that best protect cost by avoiding total stoppages and judicial suspension orders.
Rabe et al. [60] (2020), Qualitative	OR	Starting works under preliminary NDRC approval before resettlement is resolved, and overlapping construction and resettlement, are the documented strategies that enabled progress, although in contexts of underestimated compensation schedules they produced cost overruns of up to 607%.	Setting the land-compensation schedule contractually in advance and realistically, backed by independent valuation, is the condition that protects the budget against price escalation due to delayed acquisition.
C3.3 Impact on scope—C3. Impact on performance
Bathla [61] (2024), Qualitative	OR	Construction on available fronts up to the limit of the blockage (Dwarka Expressway, 14 years of litigation) made it possible to advance 90% of the corridor, but the unresolved restriction over the NPV colony permanently fragmented the scope.	The case documents that imposing a surface design on consolidated informal settlements crystallizes the fragmentation of the scope. The only verified way out was redesign as an elevated roadway on pillars: evasive engineering from pre-investment is the condition that the case shows as decisive for preserving the corridor.

OE = Object: strategy; OR = Object: restriction; OER = Object: combined. IFC: International Finance Corporation.

presents the thematic synthesis of the 51 studies in the corpus. Each row corresponds to one article and includes the following columns: the analysis subcategory with its full denomination; the author, reference number and publication year; the methodological approach used in the study; the article’s key terms as they appear in the source text; the article’s object, indicating whether the study mainly analyzes the land access restriction (OR), the execution strategy (OE), or both dimensions simultaneously (OER); the main finding with the empirical evidence reported by the author; and the contribution to right-of-way management [4], which describes how that finding contributes to knowledge on execution strategies under land access restrictions. Of the 51 articles, 19 correspond to OR (37.3%), 13 to OE (25.5%) and 19 to OER (37.3%). The table is the empirical basis of the comparative analysis developed in the Discussion section.

4. Discussion

4.1. Land Access Restrictions

Three strategies concentrate the evidence on acquisition and formal expropriation: contractual classification of the risk, anticipated negotiation, and the use of restricted eminent domain as a last resort.

Quantitative evaluations indicate that the contractual classification of failure to hand over the site as an external risk protects the contractor’s budget and schedule by exempting them from penalties for exogenous delays in the execution of civil works [13]. Complementarily, mixed-method research demonstrates that imposing forced judicial consignment of compensation funds after the failure of agreements triggers community rejection, recommending the opening of genuine negotiation spaces to prevent territorial blockage from stopping the machinery [16]. Qualitative studies focused on legal frameworks confirm that executing expropriation through eminent domain transfers the dispute directly into prolonged bottlenecks in the courts, suggesting that this coercive mechanism should be restricted to a last-resort use so as not to stall the project’s start [32].

Three mechanisms concentrate the evidence on acquisition, with opposite returns depending on when they come into play. Classifying the late-handover risk contractually protects the contractor’s budget whenever it is agreed at the tender stage [13]. Forced judicial deposit of the funds and eminent domain, used as a first resort rather than a last one, instead drag the works into prolonged litigation that judicializes the critical path [16,32]. However broad it may be, the expropriation power does not release the right of way while the conflict persists [16,32]; what releases it is exhausting negotiation before physical entry onto the land. The corpus’s negative outcomes thus betray a deferred negotiation replaced by coercion, not an invalid acquisition strategy.

In the face of social and informal conflicts, the evidence converges on three responses: transparent deliberation, anticipated demographic census and preservation of existing built fabric.

Studies that analyze the development of ring roads demonstrate that the spatial integration of existing informal properties within the road corridor’s development plans prevents community resistance to the abrupt expansion of rights of way [22]. Evidence from megaprojects in West Africa shows that performing precise population estimates and impact censuses before issuing demolition notices makes it possible to formulate viable resettlement plans that neutralize social protests at the worksite [22]. Complementarily, qualitative research highlights that adopting construction schedules structured in public phases reduces the uncertainty of informal occupants, facilitating their peaceful relocation without requiring the use of coercive force [22]. Urban governance analyses add that establishing clear tenure policies that protect occupants without formal title prevents housing vulnerability from becoming an insurmountable obstacle to the deployment of heavy equipment [22].

In parallel, evaluations of intercity toll-road projects reveal that applying independent appraisals based on real market value to determine compensations deactivates the radicalization of residents who block the advance of machinery [33]. Research on judicialized expropriations further indicates that delivering payments through transparent, direct channels, without broker intermediation between the acquisition committee and owners, prevents physical blockages caused by perceived opacity in the compensation process [33]. Complementarily, studies focused on the execution of road sections propose that eliminating intermediaries through direct deliberation between acquisition committees and owners prevents construction paralysis caused by barricades and physical resistance [33]. Likewise, conflict-analysis frameworks show that integral and direct payment of indemnities, without arbitrary tax deductions, secures the liquidity of those affected to acquire replacement land without sabotaging the expressway’s schedule [33].

The social outcome is decided by anticipation and transparency, not by the mere act of compensating. Integrating informal properties into the alignment, censusing the population before issuing demolition notices, and appraising at market value with independent assessors defuse community resistance [22,33]. Mass demolitions backed by court orders, given populations whose numbers were underestimated, instead trigger the sabotage and judicialization that halt the work fronts [22,33]. A governmental authorization does not open the way for the machinery; what opens it is having restored livelihoods and ordered the transition before moving the excavators. When conflict erupts, what failed was the timetable of that restitution.

In the face of restrictive regulatory frameworks, the studies document three unblocking mechanisms: exceptional legislation, legal reclassification of land and decrees of national priority.

Studies that analyze high-speed railway projects show that implementing exceptional legislative instruments, such as hybrid bills, grants automatic development consent that authorizes compulsory purchase of the land, bypassing municipal planning laws and accelerating physical acquisition [18]. In parallel, research on megaprojects in emergency contexts reveals that issuing executive decrees to designate infrastructures as national priorities makes it possible to block legal protections and suspend mandatory prior consultations, ensuring uninterrupted progress of civil works over historically disputed territories [35]. Complementarily, evaluations of coastal infrastructure indicate that altering spatial zoning and the regulatory classification of submerged areas as obliterated lands operates as an administrative State strategy to legally extinguish tenure rights without paying compensation, facilitating the construction of toll roads and sea dikes [20].

At the community scale, evidence from inter-regional transport corridors shows that the registration of collective titles under new land laws constitutes an institutional tactic used by excluded populations to force their financial integration into the project before expropriation [34]. Qualitative analyses also identify that the strategic construction of temporary traditional settlements on the projected alignment functions as a physical–legal mechanism to force promoters to recognize customary rights [34].

The dividing line is whether the exceptional rule recognizes the social liability or evades it. Hybrid bills and national-priority decrees accelerate territorial possession while preserving the formal acquisition and compensation schemes [18,35]. Reclassifying the land or extinguishing tenure through legal shortcuts to avoid payment, by contrast, provokes judicial resistance that halts the works for years [20]. Excluded communities know this logic and use the legal framework itself, the registration of collective titles and customary occupation, to force their financial inclusion before expropriation [34]. Concentrating expropriation authority pays off only if fair appraisal and compensation are not suppressed; without them, the State extinguishes the right on paper and loses physical access to the land.

4.2. Execution Strategies

Geometric design optimization, underground tunneling and modular execution are the three physical responses with the strongest empirical support for evading land access restrictions by reducing the surface footprint.

Studies that analyze design–build contracts show that geometric design optimization through alternative technical concepts enables contractors to design around physical obstacles and directly eliminate the need to expropriate conflicting parcels [6]. Complementarily, research on federal roads reveals that altering the original road alignment constitutes a structural modification applied to bypass consolidated informal developments without requiring their mass demolition [2]. Evaluations of urban infrastructure further indicate that choosing low-invasion construction methods, such as tunneling technology instead of cut-and-cover trenches, drastically minimizes surface-level building disruption and avoids the need for land eradication [37].

At the spatial scale, qualitative analyses identify that the impossibility of resolving land-tenure chaos forces abandoning the surface alignment and reactively redesigning the infrastructure through a structural topography of tunnels and viaducts to bypass territorial conflict [36]. In parallel, evidence from Asian projects shows that applying sectional-handover clauses makes it possible to fractionate road progress, operating the machinery modularly only in chainages free of disputes [2]. Studies focused on delay analysis confirm that adopting advanced building–information–modeling tools in early phases prevents spatial design errors and facilitates constructive readjustment in the face of land restrictions [38].

Read through real-options theory, technical flexibility pays off only if it is acquired early. Concessions structured at the pre-investment stage incorporate alternative designs and advance [6,37]; works that improvise during construction collide with deeply rooted communities [2,36]. Treating the restriction as a boundary condition from the feasibility stage is what distinguishes a manageable restriction from a stoppage. The technique is not refuted by the cases that fail: in them, what gives way is the moment of the decision, not the instrument.

Algorithmic predictive modeling, geospatial surveying and multi-criteria evaluation indices emerge as the operational tools with the strongest support for anticipating and quantifying delays due to land unavailability.

Studies that analyze forecasting methods show that implementing multiple regression equations enables planners to calculate the exact duration of the right-of-way acquisition process based on the condemnation rate and the number of parcels [4]. Predictive evaluations indicate that using machine learning algorithms, such as Random Forests, more accurately calibrates the schedule floats needed to absorb land acquisition in early planning phases [39]. In parallel, artificial intelligence models applied to infrastructure reveal that artificial neural networks integrated with land-requirement variables manage to estimate the actual project duration with statistically minimal error margins [21]. Parametric research confirms that applying partition algorithms over neural networks objectively prioritizes late acquisition as the predominant factor, directing resources toward anticipated release [45]. Stochastic analyses document that using Monte Carlo simulations and tornado diagrams mathematically isolates the cost of land-related uncertainty to mitigate financial interests during construction [44].

On the geospatial plane, research focused on land certification highlights that deploying Unmanned Aerial Vehicles for the rapid production of orthophotos accelerates cadastral titling and enables physical work to start with only partially released land [14]. Complementarily, evidence from geographic information systems shows that the satellite overlay of the project’s footprint makes it possible to identify and classify impacted assets accurately, strictly delimiting indemnity costs [42].

Methodological research additionally shows that applying fuzzy set theory allows managers to quantify expert subjectivity in order to financially prioritize resettlement contingencies before works begin [41]. Likewise, multi-criteria evaluations point out that combining the Analytic Hierarchy Process with the Entropy method eliminates biases in risk weighting, isolating the real impact of delayed compensation payments [46]. Complementarily, analyses of variance identify that the administrative digitization of cadastral files drastically reduces site-clearance time by suppressing bureaucratic bottlenecks [5]. Studies on customary settings emphasize that the anticipated calculation of a land-related social risk index identifies conflictive parcels and makes it possible to design consultation strategies before the machinery stops [43]. On the structural plane, analytical frameworks applied to megaprojects illustrate that implementing a risk breakdown structure from the feasibility phase shields the budget against the acquisition of unforeseen areas [12]. Tender frameworks add that adopting mathematical pre-qualification systems filters bidders, ensuring that only solvent contractors take on the transfer of land-related risk [40].

Forecasting does not eliminate the uncertainty of landowners’ behavior: its value is not to fix a date but to dimension the float with which the schedule absorbs the delay, an option that buffers it without claiming to suppress it. The studies themselves report those margins, wide in the parametric models [4,39] and minimal in the neural networks [21]. Management is the family most studied as an object and, even so, the institutional capacity that makes it effective, structuring risk from the outset, is not measured in any study of the corpus.

Socio-political mediation, financial integration of resettlement and adaptation of compensation frameworks concentrate the evidence on territorial legitimization: these are the mechanisms that the corpus most consistently associates with uninterrupted progress of the works.

Studies that analyze financing schemes in Sub-Saharan Africa show that the anticipated incorporation of the total resettlement costs into the initial project budget significantly reduces site-access blockages arising from lack of liquidity and delayed payments [50]. Complementarily, research on Asian regulatory frameworks reveals that the institutional authorization of exceptional extra-contractual or ex gratia payments manages to unblock land acquisition under customary-rights regimes that lack formal titles [51]. Evaluations of coastal projects indicate that applying government regulations to classify flooded parcels as destroyed land and to grant spiritual funds resolves the legal stalling, enabling the construction of mitigating infrastructure [19]. Statistical analyses of variation orders highlight that administrative containment through the definitive resolution of property disputes before awarding tenders constitutes the priority preventive measure to safeguard the geometry of the original scope without requiring redesigns [15].

On the socio-political plane, studies focused on local wisdom identify that the continuous involvement of customary authorities as mediators, in parallel with the preparation of alternative livelihoods, deactivates community resistance on ancestral lands throughout all phases of the works [47]. Likewise, public-policy models applied to toll-road projects propose that adopting hybrid communicative planning makes it possible to formulate written community-benefit agreements, transforming resistance into binding consensus before the machinery is deployed [52]. In parallel, qualitative research on pastoralist corridors documents that channeling infrastructure interventions as mechanisms of historical redress and land titling empowers communities and facilitates the integration of the physical alignment into their development plans [48]. Complementarily, evidence from highways in southwest China illustrates that political micro-mediation carried out by local village cadres is indispensable to pacify intra-family disputes over the distribution of compensations after the destruction of sacred cultural elements and the relocation of households [7].

Research on public–private partnership schemes additionally shows that delegating direct management of the land-related unblocking to corporate concessionaires through long-term agreements facilitates infrastructure execution by aligning corporate incentives with the resolution of land blockages [49]. Similarly, analyses of urban megaprojects reveal that the private operator’s deployment of atomized, individualized negotiation strategies fractures collective communal resistance and ensures the rapid physical release of parcels [17].

The contrast depends on the safeguard framework and, above all, on the promoter’s incentive. Communicative planning and mediation with leaders preserve cohesion [47,52]; atomized, house-by-house negotiation produces marginalization and fragmentation [17]. The underlying difference is budgetary: projects subject to multilateral standards reconstitute livelihoods with guaranteed financing [50], while self-financed public–private partnerships leave that social cost off their balance sheet [17,49]. Hence restitution must be resolved before tendering [47,51,52]: shifting it to the execution phase turns a foreseen safeguard into an open conflict.

Governmental assumption of land acquisition, dynamic renegotiation clauses and liquidity guarantees are the contractual instruments that the corpus identifies as a condition of financial viability in the face of land unavailability.

Studies that analyze financing models show that contractually assuming exclusive responsibility for land acquisition and resettlement by the government attracts private capital and reduces social instability in four-lane highway megaprojects [53]. Complementarily, research on success factors reveals that the rigorous allocation of land-related risk to the most capable party and the structuring of complete legal frameworks prevent paralysis in the physical execution of concessioned tunnels and bridges [10]. Parametric evaluations indicate that creating specialized units and implementing open competitive tendering shields contracts against manipulation and corruption arising from territorial blockages [9].

On the operational plane, analyses of concession models identify that incorporating clauses for automatic extension of the concession period and dynamic tariff adjustments enables the contractor to recover investments when critical delays in right-of-way release occur [54]. In parallel, research focused on emerging markets highlights that deploying permit-processing systems centralizes applications and eliminates the bureaucratic bottlenecks that stall the start of civil works [8]. Governance frameworks further note that securing a minimum public equity stake of 40% within the Special Purpose Vehicle strengthens institutional oversight and aligns the concessionaire’s decisions with the resolution of spatial obstacles [8].

Evidence from urban transport infrastructure shows that structuring blended financing mechanisms and issuing climate bonds diversifies capital sources, reducing exclusive dependence on toll revenues, which are eroded by corridor blockages [8]. Likewise, long-term viability studies propose that integrating contingency reserve accounts and governmental minimum-liquidity guarantees cushions the financial impact of stoppages forced by community conflicts [54]. Complementarily, cross-country comparisons document that implementing value-capture mechanisms and innovative financing structures diversifies the recovery of operational costs in the face of demand shortfalls and expropriation litigation [9].

Land release is a public risk; transferring it contractually to the consortium reproduces the pattern of financial asphyxiation that the corpus records again and again [10,53]. The result changes with supervision: consolidated administrations with open tendering absorb the contingencies [9,54], while fragmented regulators are trapped in endless renegotiations through permissive clauses that reward opportunism [8]. The concession contract is not the flaw; the flaw is assigning the release risk to a party that cannot bear it.

The four documented families are not alternatives to each other but responses that operate at different moments of the project cycle. C2.1 acts in the design phase by reducing the surface area that the project needs to release [6,36,37]. C2.2 computes, during planning, the real floats that land acquisition requires [4,21,39]. C2.3 must be activated before tendering, a condition that Gatitu et al. [15] identify as the third preventive factor with the strongest empirical support. C2.4 formalizes the conditions in the contract that make it possible for the previous three to operate without destroying the financial structure [2,10,53]. The corpus documents them separately; no study articulates them as a system.

4.3. Impact on Performance

The corpus shows that schedule is the most documented performance dimension: the strategies that allow progress with partially available land are the ones that the corpus most consistently associates with the protection of the schedule in developing economies.

Comprehensive research confirms that allocating specific time contingencies for land acquisition from the planning phase constitutes the preventive measure with the strongest empirical support for safeguarding the schedule [11]. In parallel, parametric evaluations indicate that incorporating time-extension clauses and tolerating partial land blockages in design–build contracts is indispensable to cushion the impact when the land is not released at the start of the works [3]. Complementarily, a study based on 111 public infrastructure projects in Sarawak show that formalizing time extensions makes it possible to maintain operational productivity and legally transfer the responsibility for the delay to the state promoter, supporting realistic scheduling based on risk profiles built from historical data of previous works [57].

Studies that analyze high-social-complexity scenarios reveal that segmenting the corridor into independently executable sections facilitates continuous physical progress by isolating local disputes [55]. Evidence from developing regions illustrates that relocating work fronts and starting operations from available chainages succeeds in replacing total stoppages with fractionated progress [57]. Statistical analyses of high-institutional-complexity settings confirm that direct negotiation with tribal leaders and community sensitization operate as unavoidable operational responses to mitigate land-related impact and ensure schedule compliance [56].

On schedule, accelerating construction does not overcome the tenure barrier; what overcomes it is having built land flexibility into the tender. Risk profiles constructed from historical data and time-extension clauses allow resources to be reassigned to the already-released fronts without incurring penalties [55,57]. The contract must assume that the works will advance over fragmented possession; programming on the opposite assumption is the true source of the schedule deviations, more than the construction method itself.

On cost, the evidence identifies two mechanisms with the strongest support: budgetary separation of land-related risk and physical reconfiguration of the alignment to reduce the expropriable surface.

Studies that analyze international financing schemes show that separating the land-compensation budget from the construction budget and advancing it as an enabling condition for the main contract protects the project’s cost structure vis-à-vis international creditors [58]. Complementarily, research focused on Asian infrastructure reveals that starting works under preliminary approvals before resettlement is resolved and overlapping construction with resettlement make it possible to maintain physical progress of the corridors [60]. Evidence from public projects in the same region indicates that independent package-based execution and alignment modification with station relocation are the documented responses that best protect cost by avoiding total stoppages and judicial suspension orders [59].

On cost, making the alignment flexible is not what contains the budget: what contains it is decoupling the land risk from the construction cost before tendering. Separating land compensation into trusts or irrevocable parallel allocations, with independent appraisals, isolates the contingency from the social conflict [58,60]. When that risk is mixed with the construction budget and execution is fragmented under delivery urgency, litigation erodes profitability and the extreme cost overruns on record appear [59,60]. What is decisive is the sequence: first secure the compensation, then build.

On scope, the corpus documents a single case with this dimension as the prioritized object. The analysis confirms that no strategy in the corpus reports verified positive impact on scope: the only available evidence documents how the absence of an integrated strategy from the design phase transfers the power to define the final scope to actors other than those who originated the project [61].

The case study of the Dwarka Expressway in Delhi shows that the State used a fragmented construction strategy, advancing construction along undisputed sections up to the exact limit of the blocked settlement; this maneuver operated as a deliberate mechanism to signal to informal occupants that expropriation was an imminent and inevitable eventuality, what the author calls governing through uncertainty [61]. To unblock the legal stalemate that prevented access to the New Palam Vihar colony, the state prosecution argued before the courts that modifying the original alignment harmed the public interest through loss of fuel efficiency and infringed on the property rights of real-estate investors who had already acquired plots along the corridor; that argument enabled the eviction of approximately 650 families to legally planned plots after years of negotiations and litigation [61]. The same study additionally documents that the affected communities used public-interest litigation to paralyze the machinery, expose the State’s irregularities and force it to apply the 2010 Resettlement and Rehabilitation Policy, turning schedule delay into a negotiation mechanism that allowed them to transition from informal precariousness to the formal acquisition of properties [61].

Once the land blockage was resolved, the project’s scope mutated structurally and irreversibly: the corridor was redesigned as an access-controlled toll road, elevated on pillars above its original alignment, becoming a physical barrier that excluded the low-income local population and triggered rapid gentrification capitalized on by real-estate developers and the State itself [61]. The study thus confirms that the alteration of scope was not a technical consequence of the land access restriction but the result of the sequence of decisions adopted: building up to the limit of the conflict, litigating the straight alignment as a matter of public interest and deferring redesign until pressure from investors and the organized middle class imposed a solution that changed both the form and the beneficiaries of the corridor [61].

The evidence from this study, although unique in the corpus in its focus on scope as the prioritized dimension, reveals a mechanism that the C2 studies document as a latent risk without naming it as such: when the infrastructure design is conceived under the assumption of full land availability and the land access restriction is managed reactively during execution, the original scope is not recovered but rather replaced by one conditioned by the balance of forces between the State, investors and communities at the moment of unblocking; the land access restriction unresolved at the design stage not only consumes schedule and budget but also transfers the power to define the final scope to actors other than those who originated the project.

The corpus documents scope as the least studied dimension: a single case illustrates how geometric design alteration and emerging social negotiation operated as last-resort mechanisms in the face of land-related litigation unresolved at the design stage.

Studies that analyze urban corridors show that the initial imposition of a surface alignment over consolidated informal settlements crystallizes permanently fragmented infrastructure throughout the construction period [61]. Qualitative evaluations indicate that the judicial paralysis of these works does not strictly constitute a planning failure but rather operates as a productive mechanism of social and political friction [61]. Complementarily, research on extended urbanization reveals that marginalized communities strategically use this temporal uncertainty to force the State to implement formal housing resettlement policies [61]. Evidence from Asian megaprojects shows that coercively forcing linear expropriation without contemplating escape valves subjects the infrastructure to stoppages that nullify the original logistical purpose of the design [61].

On the spatial plane, analyses of territorial conflicts document that the definitive strategy to preserve the planned scope consisted of completely redesigning the blocked section as an elevated highway on pillars [61]. Likewise, studies focused on land disputes highlight that to achieve a positive impact on the project, the technical flexibility of redesign must necessarily interoperate with the community demands emerging from below [61]. Analytical frameworks on infrastructure suggest that combining grade separations with land regularization processes makes it possible to deactivate the social blockage by absorbing contingencies rather than confronting them head-on [61].

Scope is not preserved by tolerating the delay, but by conceiving from the design stage a topographically separated engineering able to dialogue with the negotiated compensation schemes [61]. When the alignment is judicialized by insisting on surface development, litigation ends up turning the original geometry into an urban barrier that excludes the local population. The fate of the scope is decided in choices prior to tendering: postponing the redesign until the unblocking is what, in the only available case, cost the planned corridor.

Placed against prior research, these findings fulfill three functions. They validate the consolidated evidence that land acquisition is a primary driver of time and cost deviation [3,11,56,59]. They extend the literature, scattered across sectoral lines, by organizing the responses into four families and identifying the moment of activation as their condition of effectiveness. And they challenge the dominant explanation: studies that applied the same instrument to the same type of restriction obtained opposite results depending on whether the institutional support framework existed [19,20], and the same pattern recurs in public–private partnership, engineering and resettlement contracts [3,49,50]. The deciding factor is neither the strategy nor the actor but the foreseen institutional condition; judging a strategy by its poor application confuses the failure of management with that of the strategy. No family is an alternative to another: they operate at different moments of the cycle, and no study in the corpus articulates them as a system or directly measures that determining condition.

Table 10. Applicability matrix of strategy families by activation timing and institutional conditions.

Strategy Family	Optimal Moment of Activation	Institutional Condition Where It Is Effective	Concrete Mechanism	Evidence (Outcome)
Technical and constructive	Design and pre-investment	Concessions structured from feasibility	Alternative designs and prior segmentation of work fronts	Positive impact [6,37]; collision when deferred [2,36]
Project management	Planning	Institutional capacity to structure risk	Dimensioned float, risk breakdown structure, predictive models	Wide float in parametric models [4,39]; minimal in neural networks [21]
Social and institutional	Before tendering	Multilateral safeguards with guaranteed budget	Phased resettlement and mediation with leaders	Cohesion preserved [50]; marginalization in self-financed PPP [17,49]
Contractual and legal	Tendering and contract	Consolidated administration with open tendering	Allocation of the release risk to the State and supervision	Contingencies absorbed [9,54]; perpetual renegotiation with permissive clauses [8,10,53]

synthesizes the applicability of the four strategy families according to the moment of activation and the institutional condition, integrating the findings of the discussion and the reviewers’ observations. The matrix shows that no family is universally effective: each one pays off when it is activated at its moment of the cycle and the institutional condition that sustains it exists, and produces the opposite outcome when its activation is deferred or the promoter externalizes the risk. The land access restriction is therefore managed as a system of activatable families and not as a choice among alternatives.

4.4. Limitations and Future Directions

This review presents several limitations. The search was restricted to Scopus and Web of Science and to open access records (filter FB7), which excludes gray and paywalled literature and may bias the sample toward open-funding regions and publishers. The corpus is methodologically heterogeneous, so the synthesis is thematic and not meta-analytic: no aggregate effect size is reported, and the conclusions derive from thematic patterns, not from direct measurements of impact. The MMAT appraisal indicated high quality but identified recurrent reporting gaps, in particular the non-response risk in survey studies. The evidence is also geographically unbalanced: the findings correspond mostly to common-law or centralized administrative frameworks, and their applicability to civil-law systems with communal or indigenous land is not verified in the corpus. Finally, the corpus documents projects that persisted over time and almost no case of projects abandoned before materializing, the Brazilian high-speed train [12] being the closest reference, so that the counterfactual of failure is not measured.

The findings on effectiveness correspond mainly to projects under common-law or centralized administrative-law frameworks, whose applicability to civil-law frameworks with ejido lands and indigenous communities is not verified in the corpus.

The five Latin American cases documented in the corpus precisely illustrate the indicated limits of transferability: in Mexico, the Tren Maya and the Interoceanic Corridor resorted to emergency decrees to bypass legal protections over ejido and indigenous lands, accelerating occupation but transferring the conflict to the ordinary judicial system [35]; in Colombia, imposing concessions on populated geographies without settling tenure triggered the rejection of international consortia in the absence of contractual frameworks that absorbed late expropriations [9]; in Brazil, the first high-speed line failed commercially due to the lack of a land-related risk breakdown structure from pre-investment [12]; in Peru, the Yellow Line released the alignment through atomized negotiation that cleared the corridor in the short term but destroyed the economic-subsistence networks of the displaced [17]; in Colombia again, the Amazon showed that imposing a rigid linear design on informal tenures forces late redesign toward elevated megastructures [36]. The five cases converge on a pattern: the strategies documented in the corpus operate with greater effectiveness under centralized administrative-law frameworks; their applicability to civil-law systems with ejido land, indigenous communities and customary rights requires institutional adaptation that the corpus has not measured.

From these limitations five future lines follow. The first is to cross the type of restriction, the strategy family and the institutional capacity of the promoter, today documented separately and without measuring that capacity. The second is temporal activation: the pattern by which strategies foreseen from the pre-investment stage show positive impact and reactive ones a mixed or negative impact has not been measured. The third is geographical: road concession programs in Peru, Colombia, Brazil and Mexico have scarce indexed representation. The fourth, methodological, is the differentiated effect of strategies on scope, documented in a single case. The fifth, the most prospective, is to empirically test the recent solutions and the new construction models, modular, off-site and predictive, in projects with these land conditions, including those that today are given up for lost before they begin.

A fourth, methodological, front is the differentiated effect of strategies on project scope: the corpus documents this dimension in a single article, so future research should study how the different strategy families preserve or modify the original scope when applied to the same type of land access restriction.

The applicability of the four families varies along three institutional axes that the corpus allows us to distinguish. Between developed and developing economies the nature of the blockage changes: where cadastres and compensation are consolidated, early acquisition is feasible; where institutions are weak at anticipating conflict, litigation and informal occupation predominate [20,34]. Between public–private partnerships and traditional public works, the former shift the release risk to the consortium and require explicit contractual guarantees so as not to compromise their financial balance [10,53], whereas in the latter that risk remains with the state promoter and is managed through direct supervision [9,54]. Between centralized and fragmented governance, concentrating expropriation authority accelerates possession when it preserves compensation [18,35], but leads to judicialization when it evades it [20]. Table 10 orders these correspondences between institutional context and strategy family.

5. Conclusions

This review of 51 indexed articles identifies and classifies four families of road execution strategies against land access restrictions: technical and constructive, project management, social and institutional, and contractual mechanisms. The corpus documents strategies in 64.7% of the studies but only 25.5% examine them as an object: the solutions were in the evidence, unsystematized, which explains why the field had not produced an operational synthesis. The four families are not alternatives to each other: they operate at different moments of the cycle (design, planning, tendering and contract) and function as a system whose effectiveness depends on the type of restriction, the moment of activation and the institutional condition; no study in the corpus articulates them as such or measures that condition. When the same strategy obtains opposite results against the same restriction, the difference lies not in the strategy but in the institutional capacity that sustains it, a determining variable that is nonetheless controllable by design, not an attribute of the actor.

The documented land access restrictions correspond to three types: formal acquisition and expropriation, social and informal conflicts, and regulatory and institutional framework. The origin of the blockage varies by type: in formal expropriation, appraisal disputes and judicial litigation predominate; in informal conflicts, the absence of census and direct compensation predominates; and in the regulatory framework, institutional weakness in anticipating legal vacuums predominates. In all three cases the institutional context of the promoter determines the severity of the impact, and the type of restriction determines the applicable strategy family.

The impact on performance is unevenly documented. Land access restrictions produce schedule extensions of up to 915 days, cost overruns of up to 607% of the baseline budget and permanent discontinuities in scope when no strategy is applied or when it is activated reactively. The corpus documents the same pattern in PPP, EPC and resettlement contracts: the strategy was adequate for the type of restriction but was activated without the necessary institutional conditions. Only nine of the 51 articles have the effect of strategies on performance as the prioritized dimension, and only one addresses the impact on scope. The strategy–result relationship remains poorly documented in the corpus.

In developing economies, full availability of land before starting the works is rarely achieved. Treating the restriction as a planning variable, rather than a contingency, and activating each family at its corresponding moment, distinguishes the projects with positive impact from those that accumulate deviations of up to 915 days of schedule and 607% of cost. Future research must cross the restriction, the strategy and the institutional capacity, measure temporal activation and test the recent construction models in projects with these land conditions.