Search Results (616)

Sustainable development is crucial worldwide. Under the Paris Agreement, countries commit to Nationally Determined Contributions (NDCs) assessed every five years. China, a major contributor to global warming, has made significant efforts to reduce carbon emissions and achieve carbon neutrality, a key strategy for sustainable development. However, there is a lack of adequate attention to embodied emission reduction in rural residential construction, despite a surge in building to improve living standards. This paper evaluated the feasibility of applying a multi-ribbed composite wall structure (MRCWS) in rural China through a village service project. A full-scale shaking table test was conducted to study its seismic performance. Carbon emissions were analyzed using process-based life cycle assessment (P-LCA) and the emission-factor approach (EFA), while costs were estimated using life cycle costing (LCC) and the direct cost method (DCM). These analyses focused on sub-projects and specific structural members to validate the superiority of this prefabricated structure over common brick masonry. MRCWS blocks were prefabricated by mixing wheat straw with aerocrete, utilizing agricultural by-products from local farmlands, thus reducing both construction-related carbon emissions and agricultural waste treatment costs. Results show that this novel precast masonry structure exhibits strong seismic resistance, complying with fortification limitations. Its application can reduce embodied carbon emissions and costs by approximately 6% and 10%, respectively, during materialization phases compared to common brick masonry. This new prefabricated building product has significant potential for reducing carbon emissions and costs in rural housing construction while meeting seismic requirements. The recycling of agricultural waste highlights its adaptability, especially in rural areas. Full article

To evaluate the fire safety performance of the joint region in prefabricated buildings, specifically when the grout in the slurry layer is under an unconstrained state. Total 54 pull-out specimens were designed to investigate the effects of elevated temperatures (20 °C, 200 °C, 300 °C, 400 °C, 500 °C, and 600 °C) and steel bar positions (center, mid-side, and corner) on the bond behavior between the grout and steel rebars. The failure modes, bond strength, ultimate displacement, and load–slip curves of the specimens were recorded. The peak load of the specimens with the temperature increasing first rose and then declined, exhibiting a trend consistent with the variation in compressive strength of the grout with temperature. At 600 °C, the ultimate loads of the center, mid-side, and corner specimens decreased by 53.46%, 52.53%, and 51.28%, respectively, compared with those at ambient temperature. At ambient temperature, the bond strength of the mid-side specimen was 11.24% lower than that of the central specimen, but 19.98% higher than that of the corner specimen. At 500 °C, the bond strength of the mid-side and corner specimens decreased by 15.76% and 39.26%, respectively, compared with that of the center specimen. The failure mode changed from steel-rebar fracture to pull-out failure due to the high temperature exposure and the steel rebar position. Finally, based on the post-heating strength test results of grout specimens, a bond strength calculation formula and a bond–slip constitutive model, considering both steel rebar position and temperature, were developed, achieving a correlation coefficient (R²) close to 1.0. Full article

In response to the growing interest in sustainable and material-efficient architectural solutions, this study focuses on innovative applications of engineered timber in lightweight structural systems. It investigates the material optimization and structural performance of engineered timber thin-shell structures through an integrated parametric design approach. The study compares three prefabricated, panelized building systems, gridshell, segmented full-plate shell, and ribbed shell, to evaluate their efficiency in terms of material intensity, stiffness, and geometric behavior. Using Rhinoceros and Grasshopper environments with Karamba3D, Kiwi3D, and Kangaroo plugins, a comprehensive parametric workflow was developed that integrates geometric modeling, structural analysis, and material evaluation. The results show that segmented ribbed shell and two segmented gridshell variants offer up to 70% reduction in material usage compared with full-plate segmented timber shells, with hybrid timber shells achieving the best balance between stiffness and mass, offering functional advantages (roofing without additional load). These findings highlight the potential of parametric and computational design methods to enhance both the environmental efficiency (LCA) and digital fabrication readiness of timber-based architecture. The study contributes to the ongoing development of computational timber architecture, emphasizing the role of design-to-fabrication strategies in sustainable construction and the digital transformation of architectural practice. Full article

In this paper, the synergistic strengthening mechanism of a new type of prefabricated knee brace to semi-rigid steel frame lateral resistance was experimentally and numerically analyzed. Five full-scale specimens with a control steel frame and four knee-braced configurations were tested under pseudo-static cyclic loading in order to understand the stiffness evolution, failure mode, and energy dissipation characteristics of the specimens. Results show the following: (1) The innovative integrated knee braces increase initial lateral stiffness and yield capacity by 184–242% and 91–154% compared to conventional semi-rigid frames with acceptable ductility; (2) Three different failure modes coupled brace-joint yielding (Type I), brace dominated instability (Type II) and beam buckling brace connections (Type III) are identified; (3) Finite element simulations using ABAQUS with isotropic/kinetic hardening models show good agreement with experiments for their hysteretic responses confirming In particular the ultimate failure location is identified at the lateral screw holes of beam flanges located near brace supports where the local stress is greater than 1.8f_y. The study further proposes a BIM-integrated design workflow. These results give a theoretical basis and some practical recommendations for the application of knee-braced semi-rigid systems in earthquake-resistant steel buildings. Full article

Modular construction is generally defined as a typical offsite construction approach that can improve environmental sustainability throughout the building project lifecycle. Based on this situation, identifying the strengths, weaknesses, opportunities, and threats (SWOT) while promoting this sustainable construction method effectively during the urbanisation process is essential. Generally, modular construction is a sustainable building approach that can improve project sustainability, considering the environmental, social, economic, and technological aspects. A comprehensive understanding of the basic situation of prefabricated construction is worthwhile to ensure the widespread adoption of this offsite building method. By employing the SWOT analytical framework, this study adopts a literature review approach to conduct the investigation. In terms of the project results, the core strengths of using modular construction include improving environmental sustainability, enhancing management effectiveness, and improving construction safety and quality. The major weaknesses, on the other hand, are a lack of expertise and research, excessively high initial costs, and difficulties in stakeholder coordination. On the other hand, the major opportunities include promoting the SDGs and other policies, the Industrial Revolution 4.0, and urbanisation and building demands. The main threats, however, include substitute construction technologies, imperfect building codes and standards, and a lack of social and market acceptance. Further research can increase the sample size and collect more accurate firsthand data to validate the results of the current investigation, which can increase the effectiveness of promoting modular construction in the targeted regions. Full article

To address poor seismic performance, large residual displacement, and insufficient self-centering capacity of prefabricated frame joints in building industrialization, this study proposes a novel self-centering prefabricated frame joint reinforced with shape memory alloy fiber (SMAF)–engineered cementitious composite (ECC) composites (SMAF-ECC). A validated finite element model of the proposed joint was established using ABAQUS, with comparative analyses conducted against conventional reinforced concrete (RC) and ECC-strengthened (RC-E) joint models to explore the effect of SMAF volume content on seismic performance. Results show that replacing the joint core zone concrete with SMAF-ECC significantly enhances the joint’s seismic and self-centering capabilities, reducing residual displacement and optimizing hysteretic behavior. SMAF volume content is a key factor affecting performance, with an optimal value identified and excessive content leading to fiber agglomeration and degraded self-centering ability. This study provides a feasible solution to improve the seismic resilience of prefabricated frame joints, laying a foundation for the application of SMAF-ECC in prefabricated structures. Full article

To promote the resource utilization of high-titanium blast furnace slag (HTBFS) and advance the development of lightweight prefabricated structures, this study developed a lightweight HTBFS concrete composite beam (HTC composite beam) by replacing natural gravel and sand in concrete with HTBFS coarse and fine aggregates, and incorporating fly ash ceramsite to reduce self-weight. Symmetrically two-point bending tests were conducted on five HTC composite beams with different reinforcement ratios and precast heights, one Integrally cast HTC beam, and one ordinary concrete composite beam. The failure modes, load-carrying capacities, and deformation characteristics were evaluated. The loading process was also simulated using Abaqus, and the numerical results were compared with experimental data for validation. The results indicate that HTC composite beams satisfy the plane-section assumption; increasing the reinforcement ratio improves the load-carrying capacity, and the precast height has positive effect of HTC composite beams’ load-carrying. Compared with the ordinary concrete composite beam, the HTC composite beam exhibited a 12.30% higher load-carrying capacity, smaller deflection, and better deformation capacity. Multiple energy-based indices demonstrated that HTC composite beams possess favorable post-cracking plastic deformation capacity and stiffness retention. The difference between the finite element simulations and experimental results was less than 5%, confirming both the reliability of the numerical model and the accuracy of the experimental data. An economic analysis revealed that this structural system has significant potential for carbon reduction and cost savings, with an overall saving of approximately 141,000–500,000 CNY. These findings provide theoretical and engineering support for the application of HTC composite beams in prefabricated construction and have positive implications for reducing project costs and promoting the industrialization and low-carbon development of prefabricated buildings. Full article

The growing demand for efficient, circular, and rapid construction solutions, driven by sustainability targets and global housing shortages, underscores the need to strengthen Circular Industrialized Construction (CIC). Although foundation systems significantly influence material use, embodied impacts, and construction speed, they have received limited attention within circular design frameworks. This review addresses the question: What is the current state of knowledge on prefabricated foundation systems for housing, and how do representative examples align with the principles of Design for Manufacture, Assembly, and Disassembly (DfMAD) to support CIC? A systematic literature review complemented by a narrative synthesis was conducted, and a DfMAD Compatibility Index (CI) was developed to assess the alignment of precast foundation typologies with DfMAD criteria. Thirty-four publications were identified through PRISMA-guided search procedures supplemented by snowballing. Content analysis supported the classification of relevant information and the selection of nine representative foundation typologies for CI-based assessment. Findings indicate that screw piles, EPS-based foundations, and pad footings demonstrate the strongest alignment with DfMAD principles, particularly in adaptability, installation efficiency, and material optimization. However, seven systemic barriers persist, including scarce empirical validation, limited regulatory support, and the absence of standardized design guidelines. These factors contribute to the continued reliance on cast-in-place foundations despite engineering advances. Overall, the review highlights the potential of prefabricated foundation systems to enable material circularity, value retention, and design adaptability within CIC. Future research should prioritize validated design standards, pilot-scale empirical studies, digital tools that support DfMAD-based decision making and collaboration, and broader evaluation frameworks that incorporate underexplored social and economic dimensions. Full article

Precast concrete industrial buildings are typically characterised by high fire risk due to the production or storage of materials/products having high combustion potential and the specific activities carried out in the facility. Due to the large dimensions of these buildings, common simplified and ordinary advanced methods for the determination of the fire-induced demand, both in terms of structural performance and the safety of occupants and firefighters, may be far from accurate. Most large industrial buildings rely on translucid surfaces installed on the roof to let zenithal natural light enter the building. These are typically made with polycarbonate, and lateral windows may eventually be installed. Due to the low glass transition temperature of polycarbonate, these openings can efficiently act as evacuators of smoke and heat, although they are currently neglected by most practitioners, leading to the installation of mechanical evacuators. Moreover, the shape of the roof system of such buildings, especially if wing-shaped elements coupled with either vault or shed elements are used, can naturally ease the smoke and heat evacuation process. This paper aims to provide a contribution to the characterisation of fire development in such buildings, presenting the results of both zone and computational-fluid-dynamic analyses carried out on archetypal precast industrial buildings with a typical arrangement of either vault or shed roof subjected to cellulosic fire. For this purpose, several parameters were investigated, including roof shape (vault and shed) and the effect of short or tall columns. Concerning zone models, other relevant parameters, such as the type of glazing, the installation of smoke and heat evacuators on the roof, and larger window areas, were analysed. Full article

China’s prefabricated construction industry, despite its recent emergence, faces challenges such as limited standardization, poor integration, and low industrialization. In the Engineering, Procurement, and Construction (EPC) model for prefabricated buildings, numerous risks arise due to the long project lifecycle, complex technical requirements, and force majeure factors. These risks may cause substantial project losses if not effectively controlled. This study, from the perspective of general contractors, explores risk assessment for prefabricated building projects under the EPC model to promote construction practices and enhance project resilience. The objective is to help contractors mitigate risks and ensure the smooth and environmentally responsible implementation of prefabricated projects. Risks were identified through literature review and case analysis, and a statistical process refined them into a structured index. The Analytic Network Process (ANP) was applied to assign indicator weights, establishing a comprehensive risk evaluation model. The Gray System Theory was then employed to assess the risks in a case study from Southwest China, validating the effectiveness and applicability of the proposed model. This research provides a systematic approach and theoretical support for EPC-based risk assessment, offering guidance for risk management and contributing to development in the construction industry. Full article

Buildings consume energy and are responsible for a significant portion of greenhouse gas emissions in Australia. Increased standards are being set for building thermal performance. Given the rising demand for energy-efficient housing solutions, this work explores the potential application of innovative technologies to enhance the thermal performance. Since modular construction is attracting popularity owing to numerous advantages, including its efficiency and cost-effectiveness, optimising the thermal performance is a way to further improve its popularity, particularly in diverse Australian climates. Smart materials are unique and have desirable properties when subjected to a change in the external environment. Integration of smart insulation materials in prefabricated buildings forecasts a potential to expand the horizon of thermal performance of prefabricated buildings and subsequently lead towards an enhanced energy performance. This work investigates the effects of aerogel, phase change materials (PCMs), and electrochromic glazing. To assess their potential to improve the thermal performance of a modular house, building energy performance simulations were conducted for three different climatic conditions in Australia. Individual implementation of innovative technologies and their combined effects were also quantified. The combination of the three innovative technologies has yielded total annual energy savings of 15.6%, 11.2%, and 6.1% for Melbourne, Perth, and Brisbane, respectively. Full article

Construction and demolition (C&D) waste remains a critical challenge in India due to accelerated urbanisation and material-intensive construction practices. This study integrates survey-based assessment with machine learning to identify key causes of C&D waste and recommend targeted minimization strategies. Data were collected from 116 professionals representing junior, middle, and senior management, spanning age groups from 20 to 60+ years, and working across building construction, consultancy, project management, roadworks, bridges, and industrial structures. The majority of respondents (57%) had 6–20 years of experience, ensuring representation from both operational and decision-making roles. The Relative Importance Index (RII) method was applied to rank waste causes and minimization techniques based on industry perceptions. To enhance robustness, Random Forest, Gradient Boosting, and Linear Regression models were tested, with Random Forest performing best (R² = 0.62), providing insights into the relative importance of different strategies. Findings show that human skill and quality control are most critical in reducing waste across concrete, mortar, bricks, steel, and tiles, while proper planning is key for excavated soil and quality sourcing for wood. Recommended strategies include workforce training, strict quality checks, improved planning, and prefabrication. The integration of perception-based analysis with machine learning offers a comprehensive framework for minimising C&D waste, supporting cost reduction and sustainability in construction projects. The major limitation of this study is its reliance on self-reported survey data, which may be influenced by subjectivity and regional bias. Additionally, results may not fully generalize beyond the Indian construction context due to the sample size and sectoral skew. The absence of real-time site data and limited access to integrated waste management systems also restrict predictive accuracy of the machine learning models. Nevertheless, combining industry perception with robust data-driven techniques provides a valuable framework for supporting sustainable construction management. Full article

Timber, as a renewable material, could reduce reliance on conventional construction materials such as reinforced concrete, thereby lowering carbon emissions. Its light weight, structural reliability, and efficiency in on-site assembly make it well suited to modular systems, which benefit from standardized components in both smaller- and larger-scale projects. However, existing research related to timber construction often emphasizes specific technical or performance issues, while systematic investigation of the timber module as a core building unit remains limited. This study adopts a multi-layered framework for circular modular timber construction, integrating design, structural, prefabrication and reuse perspectives to investigate timber modules, where each layer builds upon and interacts with the others. Through selected cases, the analysis characterizes how modules of different scales and forms are generated to meet spatial and functional needs, and highlights how prefabricated units support more optimized manufacturing. Furthermore, circular design principles are reinforced through reversible joints and design-for-disassembly techniques. The main findings highlight the proposed framework that positions modular units as central to design and construction, contributing to adaptable configurations and the reuse of timber components. Potential future research directions are highlighted, including the incorporation of quantitative evaluation indicators to support the assessment and implementation of circular design strategies. Full article

Construction is one of the largest industries, exerting a significant influence on the environment, economy, and society. With the growing emphasis on sustainability, efficiency, and minimizing negative impacts, it is essential to apply innovative tools and approaches across all phases of a building’s life cycle. This article focuses on the life cycle of buildings as a comprehensive process, covering stages from planning and construction to use and eventual disposal. Special attention is given to the integration of Life Cycle Costing (LCC) as a key methodology for evaluating both the environmental and economic aspects of sustainability. The presented case study compares two construction variants a prefabricated timber structure and a traditional masonry system highlighting the differences in cost distribution and economic demands. The findings confirm that the construction and operation phases account for the dominant share of life cycle costs, with their significance particularly increasing in larger projects. These results underline the necessity of comprehensive life cycle evaluation and emphasize the importance of modeling economic aspects as an integral part of sustainable construction. Full article

The objective of this article is to evaluate the viability of implementing the Design for Manufacturing and Assembly (DfMA) methodology in the design and construction of complex wooden structures with non-standard geometry. The present study incorporates an analysis of scientific literature from 2011 to 2024, in addition to selected case studies of buildings constructed using glued laminated timber and engineered wood prefabrication technology. The selection of examples was based on a range of criteria, including geometric complexity, the level of integration of digital tools (BIM, CAM, parametric design), and the efficiency of assembly processes. The implementation of DfMA principles has been shown to result in a reduction in material waste by 15–25% and a reduction in assembly time by approximately 30% when compared to traditional construction methods. The findings of the present study demonstrate that the concurrent integration of design, production, and assembly in the timber construction process enhances energy efficiency, curtails embodied carbon emissions, and fosters the adoption of circular economy principles. The analysis also reveals key implementation barriers, such as insufficient digital skills, lack of standardization, and limited availability of prefabrication facilities. The article under scrutiny places significant emphasis on the pivotal role of DfMA in facilitating the digital transformation of timber architecture and propelling sustainable construction development in the context of the circular economy. The conclusions of the study indicate a necessity for further research to be conducted on quantitative life cycle assessment (LCA, LCC) and on the implementation of DfMA on both a national and international scale. Full article