Search Results (22)

Despite growing interest in modular integrated construction (MiC) for public housing, procurement decisions remain dominated by initial cost comparisons that overlook broader social benefits. Quantitative evidence on the conditions under which these benefits can offset cost premiums is currently absent. This study identifies break-even conditions for high-rise modular public housing using a probabilistic life cycle sustainability assessment (P-LCSA). Four non-market social benefits—carbon reduction, safety improvement, waste reduction, and early occupancy—are monetized and evaluated through 10,000 Monte Carlo simulations for 17-story and 25-story public housing scenarios in Dongducheon, South Korea. Deterministic incremental social benefit–cost ratios (IS-BCRs) of 0.353 (17-story) and 0.226 (25-story) indicate that monetized benefits offset only 23–35% of cost premiums. Early occupancy dominates total benefits (87%), while Monte Carlo simulation confirms P(IS-BCR ≥ 1.0) = 0.00% in both scenarios. The contribution lies not in reporting a negative result, but in quantifying the viability gap and identifying decision-relevant thresholds. Break-even analysis shows reducing cost premiums to 8–10% as the most plausible pathway, while a hybrid package combining cost reduction, carbon pricing, and schedule compression achieves IS-BCR above 1.0. The study contributes a probabilistic decision-support framework that reframes the question from whether MiC is viable to what conditions are required for social justification. Full article

Modular integrated construction (MiC) is an innovative construction method that shifts on-site activities to a controlled factory environment, thereby offering sustainability benefits. However, current carbon management relies on labor-intensive manual data collection, causing delayed and inaccurate carbon accounting that increases greenwashing risks. Existing approaches lack real-time, automated, and trustworthy carbon tracking capabilities across fragmented supply chains. This study develops and validates the Blockchain-enabled IoT-BIM Platform (BIBP), which combines Internet of Things (IoT), Building Information Modeling (BIM), and blockchain for real-time carbon monitoring. IoT sensors automate data capture from construction equipment and BIM provides spatial visualization of carbon at the module and building levels. A Hyperledger Fabric blockchain ensures the authenticity, immutability, and traceability of carbon records. Validated on a 15-story MiC project in Hong Kong, BIBP established a cradle-to-end-of-construction baseline of 949.84 kgCO_2e/m², identifying steel and concrete as the primary hotspots (80% of material emissions). Real-time analytics demonstrated that combining high-volume ground granulated blast furnace slag (GGBS) concrete substitution, new energy sea–land multimodal transport, and 10% steel waste reduction achieves over 20% carbon savings. Furthermore, the BIBP automated data acquisition and calculation, improving assessment efficiency by 92.4%. The platform demonstrates the potential to transform carbon management from a static, retrospective evaluation into a proactive, data-driven monitoring process, equipping stakeholders with a tool to dynamically track emissions and make timely interventions toward carbon reduction targets. Full article

Despite its recognized advantages in sustainability and efficiency, the widespread adoption of Modular Integrated Construction (MiC) is impeded by transaction costs (TCs). While previous studies have cataloged numerous barriers, a systematic, quantitative synthesis of their relative impact on TCs is lacking. This study bridges this gap by conducting a hybrid systematic review and meta-analysis of 37 empirical studies (2005–2025) to identify and rank the key drivers of TCs in MiC. Grounded in Transaction Cost Economics, 32 factors were categorized into transaction attributes, the transaction environment, and stakeholder-related aspects. The meta-analysis quantified the pooled effect sizes, revealing that operational and procedural hurdles—specifically “Poor Logistics,” “Design Change,” and “Insufficient Quality Inspection Standards and Regulations”—are the most critical determinants. A key finding is the divergence between the most frequently cited barriers and those with the highest impact, underscoring the value of meta-analytic synthesis over simple frequency counts. Subgroup analyses further indicated that the severity of institutional and regulatory drivers is more pronounced in developing economies. This research provides a novel, evidence-based framework for stakeholders to develop and prioritize mitigation strategies, advocating for investments in integrated digital tools, rigorous front-end planning, and context-sensitive policy development to reduce transactional inefficiencies and promote MiC adoption. Full article

Urban built environments face unprecedented challenges in resource management and sustainability, necessitating innovative approaches that integrate circular economy principles with construction technologies. This study addresses the critical research gap at the intersection of circular city initiatives and modular integrated construction (MiC) by employing a structured literature review methodology to systematically analyze existing knowledge. Following PRISMA guidelines, the search screened 438 papers (209 on MiC, 229 on Circular City Initiatives), of which 68 papers were included after quality appraisal for thematic synthesis using MAXQDA. The analysis offers a structured basis for operationalizing circular economy principles in the construction sector and provides a roadmap for future inquiry. The research develops a conceptional requirement matrix framework that bridges circular city principles with MiC implementation. Through systematic analysis, the study establishes six key requirements for construction technologies resulting from circular city initiatives and evaluates them against the six key MiC characteristics: prefabrication and assembly; speed and efficiency; quality and safety; standardization and mass production; sustainability; integration with technology. This matrix represents the first systematic approach to operationalizing circular economy principles through modular construction methodologies. The framework reveals that MiC constitutes a transformative paradigm for circular urban development through multiple synergistic pathways: prefabrication enhances reversibility and durability, extending service life and enabling material loop closure; eco-design integration improves safety and quality standards; deconstructability facilitates adaptive reuse; and BIM-based tools enhance material efficiency and recycling capabilities. The requirement matrix demonstrates strong alignment between circular city requirements and MiC characteristics, with adaptive reuse and modularity showing the strongest correspondence. Stakeholder engagement and policy support emerge as critical enablers across all implementation dimensions. While the framework is grounded in a structured literature review, it remains theoretical and serves as a foundation for future empirical validation. Full article

Driven by the urgent need for industrial transformation and emerging technologies, the construction engineering market is rapidly evolving toward intelligent building systems. This study employs latent Dirichlet allocation (LDA) methodology to analyze 474 blockchain-related research abstracts from Web of Science and Scopus databases, identifying eight key research topics: (1) industry adoption and implementation challenges; (2) smart contracts and payment mechanisms; (3) emerging technologies and digital transformation; (4) construction supply chain integration and optimization; (5) building modeling and technology integration; (6) modular integrated construction (MIC) applications; (7) project data and security management; and (8) construction industry sustainability and circular economy (CE). Using the autoregressive integrated moving average (ARIMA) model, the study forecasts trends for the top three research topics over the next 36 months. The results indicate strong positive growth trajectories for industry adoption and implementation challenges (Topic 1) and project data and security management (Topic 7), while emerging technologies and digital transformation (Topic 3) demonstrate sustained growth. This study offers a thorough examination of the present landscape and emerging research trends of blockchain in construction, and establishes an overall framework to comprehensively summarize its research and application in the construction industry. The results provide actionable insights for both practitioners and researchers, facilitating a deeper understanding of blockchain’s evolution and implementation prospects, and supporting the advancement of innovation within the industry. Full article

With the development of prefabricated buildings, the challenge of integrating fireproofing and anti-corrosion in steel structures has become increasingly prominent. Based on epoxy resin, we developed a multifunctional coating with high-flame retardant efficiency and corrosion resistance, which can be employed in the key parts of modular integrated construction (MiC), thereby enhancing the safety of the prefabricated buildings. Experimental data showed that the fire resistance limitation reached 124 min, the salt spray resistance 2540 h, and the adhesion grade 1. The limiting oxygen index (LOI) of the cured coating was 45%, corresponding to the V-0 classification in the vertical burning test from Underwriters Laboratories Inc. (Northbrook, IL, USA) (UL 94). Compared with the latest studies, the integrated formulation exhibits simultaneous gains in fire and corrosion protection, offering a promising single-layer solution for MiC. Full article

Modular Integrated Construction (MiC) has been strongly promoted in many dense urban areas, including the Greater Bay Area. There might be an explosion risk if leaked flammable clean refrigerants accumulate in a confined unit. Experimental and modeling studies on the explosion of flammable refrigerant propane in an MiC unit were carried out with a rectangular unit model to explore well-covered or partially covered conditions, representing the scenario of an MiC unit with its door open or closed. The experimental results were used in developing an analytical model to predict the flame surface and pressure change, with acceptable results. This study could be used as a reference for estimating pressure changes and designing ventilation systems to prevent deflagration in MiC units. Full article

Hong Kong faces critical construction challenges, including workforce aging, land shortages, and near-capacity waste disposal. Modular Integrated Construction (MiC) offers a promising solution. As Hong Kong has just recently adopted the MiC, quantitative studies that explore the actual performance differences between MiC projects and conventional on-site construction projects in Hong Kong are lacking. To fill this knowledge gap, this study utilizes an extended life cycle assessment–Life Cycle Performance Assessment to conduct on-site investigations and case studies on a MiC pilot residential project and a conventional on-site construction residential project in Hong Kong from multiple dimensions: cost, time, safety, and environment. The assessment indicators include five types of greenhouse gas emissions, cost performance, schedule performance, and safety-level index. This study found that the greenhouse gas emissions of the MiC project during the entire construction period were reduced by approximately 21.60% compared to traditional on-site construction projects. The most significant part of the greenhouse gas emissions of the two methods was the embodied emissions of construction materials, accounting for 83.11% and 87.17%. Compared with the conventional construction project, the factors that actively promote the reduction of greenhouse gas emissions in the MiC project are the embodied greenhouse gas emissions of building materials, the transportation of construction waste, and the resource consumption of equipment. In addition, there is no significant difference in the safety performance index of the two construction methods, but MiC projects have more efficient schedule performance management. Surprisingly, the cost control of MiC projects is not as good as that of conventional construction projects, which differs from existing research results in other regions. Full article

Modular integrated construction (MiC) is a cutting-edge approach to construction that significantly improves efficiency and reduces project timelines by prefabricating entire building modules off-site. Despite the operational benefits of MiC, the carbon footprint of its extensive supply chain remains understudied. This study develops a hybrid approach that combines multi-agent simulation (MAS) with deep learning to provide scenario-based estimations of CO₂ emissions, costs, and schedule performance for MiC supply chain. First, we build an MAS model of the MiC supply chain in AnyLogic, representing suppliers, the prefabrication plant, road transport fleets, and the destination site as autonomous agents. Each agent incorporates activity data and emission factors specific to the process. This enables us to translate each movement, including prefabricated components of construction deliveries, module transfers, and module assembly, into kilograms of CO₂ equivalent. We generate 23,000 scenarios for vehicle allocations using the multi-agent model and estimate three key performance indicators (KPIs): cumulative carbon footprint, logistics cost, and project completion time. Then, we train artificial neural network and statistical regression machine learning algorithms to captures the non-linear interactions between fleet allocation decisions and project outcomes. Once trained, the models are used to determine optimal fleet allocation strategies that minimize the carbon footprint, the completion time, and the total cost. The approach can be readily adapted to different MiC configurations and can be extended to include supply chain, production, and assembly disruptions. Full article

Transporting precast modules via water is a vital component of multimodal transportation systems, increasingly utilized in large-scale Modular integrated Construction (MiC) projects where modules are prefabricated in remote factories. The effectiveness of module transportation planning significantly impacts the overall costs and productivity of MiC projects. However, existing studies on module transportation planning neglect the uncertainty inherent in MiC projects, thereby resulting in increased costs. This study proposes a two-stage stochastic programming model to optimize transportation planning through water, addressing this uncertainty. A real Hong Kong case study with 418 modules is employed to assess the effectiveness of the proposed model in comparison with three deterministic models. The optimal transportation plan of modules solved by the proposed model costs HKD 148,951, comprising 21% from temporary rentals and 79% from advance bookings. The results show that the three deterministic models, without considering the uncertainty in module demand, will incur additional transportation costs that are 25% higher on average than the results of the developed two-stage stochastic model. Additionally, this paper conducts a sensitivity analysis on the price ratio of pre-booked barges to on-demand barges to evaluate its impact on total transportation costs. The two-stage programming model developed in this paper can effectively help transport planners reduce the costs associated with module water transportation. Full article

The application of reinforced concrete modular integrated construction (MiC) has gained popularity in Hong Kong, but challenges still exist in the temporary tying of side walls during composite wall construction. This paper presents an innovative inner tie system for composite walls, applied in a MiC project in Hong Kong. The system’s components are installed on the side walls of precast modules in the factory without the need to penetrate through the walls. After transport to the site, by rotating the loop on-site to engage the hook, the tying effect is achieved during on-site concrete pouring between the interstitial space of two modules. This system eliminates the use of tie bolts that penetrate precast side walls, allowing for comprehensive interior fitting-out in the factory and minimizing disruptions to internal decoration during on-site construction. The paper presents the system’s mechanism, nonlinear Finite Element Analysis (FEA) simulation, section size optimization, and validation through tensile and punching shear tests. Furthermore, an instrumented mockup module assembly was carried out, and the system was eventually applied in a real MiC project. The system can effectively control the horizontal deformation of MiC module side walls within a limit. Compared to current existing tying methods, this system offers easy installation, load-bearing reliability, adaptability to certain construction errors, savings on manpower and construction time, and also a decrease in construction waste and carbon emission. It will provide a valuable reference for future MiC projects. Full article

Modular integrated construction (MiC) is now widely adopted by industry and governments. However, its fragile and delicate logistics are still a concern for impeding project performance. MiC logistic operations involve rigorous multimode transportation, loading-unloading, and stacking during storage. Such processes may induce latent and intrinsic damage to the module. This damage causes safety hazards during assembly and deteriorates the module’s structural health during the building use phase. Also, additional inspection and repairs before assembly cause uncertainties and can delay the whole supply chain. Therefore, continuous monitoring of the module’s structural response during MiC logistics and the building use phase is vital. An IoT-based multi-sensing system is developed, integrating an accelerometer, gyroscope, and strain sensors to measure the module’s structural response. The compact, portable, wireless sensing devices are designed to be easily installed on modules during the logistics and building use phases. The system is tested and calibrated to ensure its accuracy and efficiency. Then, a detailed field experiment is demonstrated to assess the damage, safety, and structural health during MiC logistic operations. The demonstrated damage assessment methods highlight the application for decision-makers to identify the module’s structural condition before it arrives on site and proactively avoid any supply chain disruption. The developed sensing system is directly helpful for the industry in monitoring MiC logistics and module structural health during the use phase. The system enables the researchers to investigate and improve logistic strategies and module design by accessing detailed insights into the dynamics of MiC logistic operations. Full article

The shift from traditional on-site to off-site construction marks a significant evolution in the construction industry, characterized by increasing levels of prefabrication. These advancements enhance construction efficiency, reduce lead times, and mitigate environmental impacts, leading to modular integrated construction (MiC). However, MiC presents complex supply chain challenges, particularly in the transportation of prefabricated components and fully integrated modules. This study addresses these challenges by employing a multi-agent simulation using AnyLogic to optimize MiC transport logistics. The simulation models the interactions of various agents involved in the MiC process to improve operational efficiency and reduce costs. Results demonstrate that using three vehicles per supplier minimizes total transport costs, effectively balancing fixed and variable expenses while eliminating penalties for project delays. The findings highlight the cost efficiency of MiC, showing potential savings due to centralized assembly and optimized logistics. These significantly reduce material transportation and related costs, contributing to the overall efficiency and sustainability of construction projects. These insights underscore the value of multi-agent simulation in addressing the complexities of MiC supply chains. Full article

As construction projects become increasingly complex, modular integrated construction (MiC) has emerged as a pivotal solution, driving integrated development in complex projects. However, the reliance on prefabricated modules underscores the crucial role of supply chain management (SCM) in MiC, necessitating strategic planning and operational control. This study aimed to use bibliometric analysis to map the SCM knowledge domain within MiC. Through the use of keywords related to “supply chain” and “MiC”, 196 relevant papers were extracted from the Web of Science database. These papers were subjected to co-citation analysis, keyword co-occurrence analysis, and time span analysis to elucidate the historical evolution, multidisciplinary domains, and future directions in planning and control within SCM-MiC. The research identified two milestones in SCM-MiC’s historical trajectory, enhancing our understanding of its foundations. Moreover, 11 clusters were identified, illustrating the multidisciplinary nature of SCM-MiC. Dividing the literature into seven stages of the supply chain, the research outlined four research directions aligned with project complexity and technological development, highlighting current hotspots and gaps of the strategic planning and control. These directions bridge the construction management and information technology domains, guiding future SCM-MiC research within complex project management. Full article

Modular integrated construction (MiC) is a new type of assembled building structure system that consists of prefabricated concrete modules connected using post-cast concrete. To reduce material consumption and realize casting without supporting molds, thin and lightweight concrete formworks (MiC formworks) with a thickness of 30 mm are installed as part of the shear wall. Due to the thinness, concrete pouring tends to cause MiC formwork cracking, mold rising, and other problems. Its stress performance and damage mechanism are not clear. For this reason, three groups of MiC formworks with different material composition types are designed. The static load test is carried out in a graded partition loading mode, and parametric analysis is combined with numerical simulation to systematically study the influence of different material components on the mechanical properties of MiC formworks. The results show that the front cracks of the MiC formworks are mainly distributed under the truss tendons, and the back cracks are mainly distributed in the span position of the adjacent truss tendons. These cracks both occur along the span direction of the MiC formworks. Increasing the concrete strength has a significant effect on improving the load-bearing capacity of MiC formworks, while incorporating steel fibers can significantly improve its deformation and crack resistance. Parametric analysis showed that the steel fiber admixture exhibited limited improvements in the cracking resistance of the panels as the concrete matrix grade increased. The research results provide a practical basis for optimizing the production process of MiC formworks. Full article