The growing demand for sustainable and adaptable construction has increased interest in modular building systems; however, conventional modular solutions often face limitations in transport efficiency and reusability. Foldable modular buildings (FMBs) provide a compact, deployable alternative that enhances delivery efficiency and on-site constructability. This study classifies four FMB types based on their deployment mechanisms, namely midcolumn fold, Z-fold, expandable fold, and 2D panelized systems. It evaluates their constructability using a weighted decision matrix derived from established modular construction decision-making criteria. The results indicate that vertically deployed systems (Z-fold and midcolumn fold) achieve the highest constructability scores due to reduced assembly complexity and lower labor demands. In contrast, 2D panelized systems offer greater design flexibility. A sensitivity analysis demonstrates that constructability preferences depend on application context, with panelized systems favored for residential use and foldable modular systems better suited to emergency and temporary buildings. Finite-element modeling of glass fiber-reinforced polymer (GFRP)-framed modules shows adequate global structural performance, although midcolumn joints reduce lateral stiffness and midbeam joints increase gravity-induced deflections. A fatigue-based serviceability assessment incorporating stiffness degradation of GFRP bolted joints indicates that fatigue effects under wind loading do not govern performance within the design life. Overall, FMBs exhibit high constructability and sufficient structural reliability, highlighting their potential for efficient, adaptable modular construction.

Inter-modular connections are vital for ensuring load sharing, transfer efficiency, and structural integrity in prefabricated modular buildings under extreme loading conditions. The existing intermodular connections in steel buildings face several challenges, including insufficient lateral load resistance, inability to reuse, higher costs, and longer installation times. Therefore, this study aims to develop a semi-interlocking bolted plate connection designed for modular buildings, offering enhanced assembly efficiency and structural performance at a lower cost. Two types of semi-interlocking inter-modular connections were developed to improve compatibility with common steel modular building sections and typical modular arrangements. Monotonic loading tests, including compressive, tensile, and shear tests, were performed to assess the connections' load-bearing capacities and deformation characteristics. The experimental results demonstrated that the connections have sufficient compressive and tensile capacities compared to the axial capacity of the column. Moreover, the shear capacity of the connections is nearly 10% higher than that of traditional bolted connections and 50% higher than existing inter-modular connections, while ensuring ease of construction. The connection performed adequately in axial and shear capacities, enabling the required or exceeding standard design capacities. Moreover, the connections were nearly 40% less costly than most of the industry's existing partially interlocking connections. The findings suggest that the proposed semi-interlocking connection is a viable solution for advancing the modular construction industry.

Tropical cyclones represent one of the most severe natural hazards affecting residential buildings in Australia, causing extensive structural and non-structural damage. Brick veneer houses, as the predominant residential construction type in Australia's existing housing stock, are subject to a range of defects, from localised elemental damage to complete structural failure. Structural retrofitting is a timely requirement for these cyclone-affected houses to enhance structural resilience while complying with updated modern design standards. Hence, a structured analysis of cyclone-related defects in the existing housing stock remains a prerequisite for implementing optimal retrofitting solutions. Numerous post-cyclone damage assessments have been conducted. However, no established structured defect database is present that facilitates detailed defect information. Thus, this study proposes a structured cyclone defect database using a hybrid Natural Language Processing (NLP) approach to extract and structure the available defect data sources. The database comprises both qualitative and quantitative information on element-level defect variations, failure mechanisms, the effect of construction cohort on identified defects, and state-based vulnerability of cyclone defects. Analysis conducted on the structured-defect database reveals that roof systems are consistently identified as the most vulnerable building element, which accounted for more than 68% of the recorded defects, followed by defects associated with wall systems and openings. Wind-induced failure is the predominant failure mechanism affecting all the elements, while contributing to more than 60% of identified defects. Debris impact and wind-driven water ingress are the other two identified failure mechanisms, collectively accounting for 30% of the defects. Temporal trends in damage patterns were also highlighted through the age-cohort analysis. State-based comparative analysis further revealed similar vulnerability patterns with regional variations, reflecting differences in cyclone exposure conditions, construction practices, and regulatory evolution. Overall, the developed structured database presents a valuable resource for cyclone vulnerability modelling, prioritisation of retrofitting solutions, and future development of predictive tools for residential resilience.

Electric vehicle (EV) adoption is rapidly increasing in Australia as well as around the world, as it is supporting national decarbonisation goals. Despite this, the battery used in EVs poses a severe fire risk when subjected to physical damage. The garage of the timber-framed house is highly prone to suffering from this unique and severe fire. As the garage's walls were designed based on the deemed-to-satisfy criteria specified by the fire resistance level (FRL), which follows the standard fire curve. However, an EV fire is non-linear and initiated by a violent thermal runaway, making it unpredictable, and these conditions were not accounted for in the traditional fire safety design approaches for timber-framed walls. This study assesses the FRL of timber-framed walls subjected to EV fires through the validated fire dynamic simulation. A timber-framed wall panel and the walls attached to the representative house garage were subjected to twelve different EV fires. Results show that the FRL of the timber-framed wall attached to the garage declines abruptly within 15 min in both structural adequacy and integrity, leading to early structural compromise and increased fire spread, ultimately resulting in both structural and thermal insulation failure under EV fires. These findings indicate that the fire resilience of the current timber-framed house design is inadequate in the event of EV fires, highlighting the need for improvements in design and construction regulations.

Incorporating recycled materials into concrete paves the way for sustainable construction while reducing landfill waste. The application of foam concrete in construction has demonstrated its potential to improve thermal insulation capacity and lower the dead load on structures, thereby enhancing sustainability. However, it has high embodied carbon and low thermal insulation when used for structural applications. Therefore, this study used waste clay bricks and recycled polypropylene fibres from face mask waste to develop an eco-friendly geopolymer foam concrete to improve the thermal and sustainability performance. Initially, the foam content of the geopolymer foam concrete mix was optimised based on the flowability, wet density and stability using different foam contents of 5 %, 10 % and 15 % by weight. Additionally, the effect of varying fibre dosages (0.5 %, 1 % and 1.5 % by volume) on the mechanical properties (compressive and flexural strength), mix homogeneity and thermal insulation characteristics were evaluated. The results showed that increased foam content resulted in a highly flowable mix, whereas reduced mix stability was attributed to a higher air content and the faster collapse of the air bubbles. However, adding fibres up to 1 % dosage improved the fresh properties and enhanced the stability of the mix. Furthermore, this also increases the flexural capacity by approximately 84 % when a 1.5 % fibre dosage is added. Based on the fresh properties and foam stability observations, a 10 % foam content was deemed optimal and adopted to develop fibre-reinforced geopolymer foam concrete. Furthermore, the compressive strength reduction for this foam content with the addition of fibre is insignificant (i.e. <= 10 %). Nevertheless, the fibre-reinforced geopolymer foam concrete exhibited low thermal conductivity (i.e. ranging from 0.245 to 0.331 W/mK) and diffusivity. This indicates that recycled fibres from face mask waste and waste clay bricks can be used to enhance the sustainability of foam concrete.

Rapid advancements in four-dimensional (4D) printing have introduced time-dependent functionality into additive manufacturing. Research trends indicate that biomedical, aerospace, and materials science disciplines primarily drive 4D printing. However, its applications in civil engineering remain underexplored, while some developed applications remain in the laboratory stage. This paper systematically examines the current progress, applications, and emerging potential of 4D printing with a focus on its relevance to civil and construction engineering. A bibliometric mapping and critical analysis were conducted. Results show that, within civil engineering, about 35 research articles were published focusing on modular self-assembling components, climate-adaptive façades, deployable bridges, and regolith-based lunar construction. However, large-scale adoption is constrained by limited materials and printing equipment, as well as the absence of performance-based standards. To transition 4D printing from experimental studies to practical applications, future research should focus on developing AI-driven predictive modelling and a formalised standardisation framework.

Soil-based 3D printing has emerged as a potential solution for sustainable construction, due to growing concerns over the environmental impact of cement-based materials. However, the limited understanding of soil printability, material behaviour, and performance under real-world conditions remains a significant barrier to its application. This review provides an in-depth evaluation of material performance and technological challenges of soil 3D printing with a special focus on the extrusion-based printing method. Furthermore, this study explores the fresh and hardened state properties of soil-based mixtures, highlighting the importance of rheology in achieving extrudability and buildability during the printing process. Notably, the incorporation of certain additives has been shown to reduce shrinkage by up to 50% and increase compressive strength by 10-30%, although results remain highly dependent on soil type. The environmental assessments indicate that soil 3D printing can reduce the carbon footprint by up to 20% compared to traditional construction methods, especially when local or excavated soils are used. Despite these advancements, challenges persist in standardising mix designs, managing variability in soil composition, and ensuring long-term durability under environmental exposure. To advance soilbased 3D printing in sustainable construction, it is important to integrate soil mechanics principles, standardise testing protocols, and validate results at the field scale.

Origami-based metamaterials offer significant potential for lightweight, compact, and geometrically programmable deployable structures. However, most existing designs face a fundamental trade-off between flat-foldability and load-bearing capacity, limiting their practical engineering applications. This study proposes a reconfigurable origami metamaterial that enables in-situ switching between a compact flat-folded state and a mechanically stable, load-bearing configuration without inducing facet deformation or modifying the crease pattern. The transition is achieved through complementary out-of-plane and parallel self-locking mechanisms based on hard-stop interactions, which drive the structure into a kinematically singular state within a rigid-origami framework. Owing to their foundation in a six-crease vertex and four-bar kinematics, the proposed mechanisms are independent and inherently scalable, allowing adaptation to a wide range of flat-foldable geometries. The concept is realised in a volumetric cuboidal unit composed of waterbomb-derived facets, termed the waterbomb-cuboid origami (WC-ori), which deploys through a single degree of freedom with simultaneous actuation. The geometric and kinematic principles governing the state transition are first established through kinematic analysis and mechanical bifurcation considerations. Experimental axial compression tests and finite-element simulations are then conducted on WC-ori prototypes fabricated from cardboard to validate the proposed load-bearing mechanism. Results demonstrate that switching from the flat-folded to the self-locked deployed configuration enhances the load-carrying capacity by approximately two orders of magnitude relative to the unit self-weight. A parametric numerical study further elucidates the influence of hard-stop geometry and folding angles on load-bearing performance and volumetric efficiency, highlighting the potential of WC-ori units for scalable tessellated structural systems.

Nuclear waste management has become a critical issue due to growing concerns about the long-term safety and sustainability of radioactive waste disposal and its impact on infrastructure. Insufficient knowledge and regulations surrounding nuclear waste management are significant challenges to sustainable development. This review provides an in-depth categorisation of nuclear waste, with particular emphasis on high-level waste (HLW), which requires extensive pre-disposal treatments, and explores its impact on infrastructure and structures. Recent innovations, such as thermal treatment, partitioning and transmutation, are highlighted for their effectiveness in reducing HLW volume and radiotoxicity. The review also examines the detrimental effects of radiation on containment materials, especially concrete and steel. Notably, containment infrastructure is vulnerable to degradation, with studies showing a loss of up to 50% in compressive strength in concrete exposed to extreme neutron irradiation and reductions of up to 70% in Young’s modulus. Advanced materials, such as fibre-reinforced concrete and oxide-dispersion-strengthened steels, offer promising solutions by mitigating these effects and improving durability by 10–30%. Furthermore, the review identifies significant strides in international collaboration on nuclear waste management, which have led to advancements in minimising hazards and improving waste processing. These efforts are further supported by the integration of digital tools and material innovations, ensuring continued progress in managing nuclear waste safely and sustainably.

Modular construction is increasingly recognized worldwide as an efficient and sustainable alternative to conventional building methods. In Australia, modular building systems have been successfully implemented to address housing shortages, rapid urbanization, and disaster relief efforts. The integration of deployable modular systems further enhances these benefits by enabling efficient transportation and rapid on-site assembly, thereby improving flexibility and resilience in urban construction. Conversely, Indonesia faces significant challenges in adopting modular construction due to regulatory constraints, economic limitations, and a shortage of skilled labor. This study conducts a comprehensive review of current modular construction practices in both Australia and Indonesia, accompanied by a comparative analysis of the regulatory frameworks, available resources, and construction methodologies in each country. The objective is to identify key challenges and opportunities for advancing resiliency in urban and post-disaster housing solutions. Furthermore, this study proposes a conceptual design recommendation tailored to post-disaster housing reconstruction in Indonesia. By incorporating deployable module systems, the proposed approach aims to address the demand for adaptable housing solutions that transition from temporary to permanent use, minimizing the need for extensive reconstruction resources.

The rapid advancement of generative AI (GenAI) has significantly influenced educational and professional environments, offering personalised support and enhanced productivity. While GenAI is known for improving learning efficiency, its impact on the learning process among civil engineering students and professionals remains underexplored. This study surveyed both groups to assess their perceptions of GenAI adoption, focusing on its influence on subjects’ perceptions of efficiency, problem-solving, motivation, teamwork, and future potential. Quantitative (Likert scale) and qualitative (thematic) analyses were used to interpret the findings. Results showed that 75% of participants viewed GenAI positively for enhancing efficiency, with perception of problem-solving identified as the most improved skill (70%). However, its perceived effect on teamwork and collaboration was limited. Students perceived stronger benefits in problem-solving and motivation perceptions, while professionals reported more consistent collaboration advantages. Concerns included over-reliance and information accuracy, reinforcing the need for ethical and critical use. This study underscores the importance of hybrid learning, combining conventional and GenAI-assisted methods, to support sustainable education and workplace adaptability in line with Sustainable Development Goals 4 (quality education) and 8 (decent work and economic growth). To ensure responsible GenAI integration, policies must encourage its use as a supplement rather than a replacement for traditional methods. Findings offer insights into how GenAI can be ethically and effectively implemented across learning and work settings. Future cross-context studies are encouraged to further explore how learners and professionals engage with GenAI, particularly in higher education and engineering practice, ensuring long-term value, collaboration, and critical skill development.

Economic inflation remains a persistent and multifaceted challenge, creating uncertainty across various sectors, particularly affecting the construction industry. As a cornerstone of financial stability, the construction sector plays a vital role in shaping nations, building infrastructure, and driving societal growth. However, amid discussions of inflation and economic trends, the mental health of the construction workforce has often been overlooked, emerging as an unrecognized casualty of inflation's impact. Despite its significance, limited attention has been paid to understanding how inflation affects the mental well-being of industry professionals. This research explores the intricate relationship between economic inflation and the psychological well-being of construction professionals. Data were gathered through an online survey completed by 155 professionals globally. Results indicated how inflation intensifies stressors such as job insecurity, financial instability, workload pressures, and safety concerns. Among the respondents, 40% indicated that they were experiencing moderate stress levels, which tended to affect their focus, mood, or behavior. Notably, 48% of respondents reported increased stress levels directly attributable to inflation, and the percentage of professionals with high stress levels increased by nearly 24% due to inflation. Moreover, inflation intensified the negative mental health effects on professionals experiencing salary reductions. The results also indicated that variations in mental health are significantly influenced by demographic factors and working environments, with high levels of statistical significance (<0.001). Additionally, the lingering effects of past stressors were evident in present mental health outcomes, with inflation acting as a critical covariate. Ultimately, this study contributes to a broader conversation about the need to prioritize mental health within the construction industry. The findings highlight key considerations for policymakers and stakeholders in shaping the strategies to foster a more resilient, supportive, and employee well-being work environment.

The rapid growth of electric vehicles (EVs) has introduced new fire safety challenges for the built environment, particularly within reinforced concrete structures. Fires involving lithium-ion batteries are substantially different from conventional hydrocarbon-fuelled fires due to their rapid heat escalation, extended burning duration, and potential for re-ignition caused by thermal runaway. This study assesses the adequacy of existing fire design standards in addressing these emerging hazards, emphasising the spalling behaviour of concrete under EV induced fire exposure. The study found that concrete structures are highly vulnerable to spalling when exposed to EV fires, as the typical temperatures initiating concrete spalling are significantly lower than the extreme temperatures and re-ignition produced during an EV battery fire. Moreover, the evidence suggests that EV fires can sustain peak temperatures exceeding 1000 °C in a short period, which exceeds the assumptions underlying standard fire curves, such as ISO 834. A comparative assessment of the National Construction Code (NCC 2022) and standards (i.e., AS 1530.4, EN 1992-1-2) reveals that current design methodologies and fire-resistance ratings underestimate the severity and duration of EV fire conditions. This study also proposes code-aligned improvements and a performance-based evaluation framework that integrates empirical EV fire curves. The findings highlight a pressing need to re-examine fire design provisions and update thermal exposure assumptions to ensure that reinforced concrete infrastructure remains structurally safe and reliable as EV adoption increases.

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.

Glue-laminated timber (GLT) is an engineered wood product widely used in mass timber construction for its strong structural and fire-resistant properties. However, the fire performance of GLT varies significantly due to the natural and uncertain phenomena (moisture, exposure time, isotropic, homogenous properties, etc.) of fire and timber. This makes it difficult to predict the fire behaviour of the GLT structural elements. To ensure building safety, it is crucial to assess GLT's fire behaviour and post-fire structural integrity during the design stages. This study conducted the experimental tests of GLT beams (280 mm x 560 mm) without loading (1.4 m) and under a four-point bending load (5.4 m). Tests identified thermal behaviour and charring rates of GLT beam. Then, the residual stiffness of the GLT beam was calculated, and the charring rates of the beams were compared with Australian and European standards. Reliability analysis was conducted for beams for a fire exposure of 120 min, considering the charring rates observed through the analysis and simulating the fire insulations. Results show that the charring rate of GLT made with spruce pine timber varied between 0.43 and 0.81 mm/min, with a mean rate of 0.7 mm/min, aligning with both Australian and European standards. However, considering timber density and moisture content, the charring rates in Australian standards were conservative. The study also found that structural capacity significantly degrades under fire, with a 22 % reduction in flexural stiffness after 120 min of exposure. Additionally, GLT beams can safely function for 30 min under 75 % of their design moment capacity and for 60 min under 50 % capacity.

Inter-modular connections play a critical role in the load sharing. Thus, this study aims to assess the impact of interlocking connections on the reliability indices of modular buildings under extreme loads. Five interlocking and partial interlocking connections were chosen for further analysis under extreme wind and earthquakes for structural reliability analysis of the connections. Fragility curves were developed for connections in axial, shear, and moments based on an analysis of a 10-storey case study modular building. Results showed that partial interlocking connections can safely function at a wind speed 60% higher than that of complete interlocking connections. Moreover, it was identified that partial interlocking connections can withstand a 2.8 times higher peak ground acceleration than a complete interlocking connection under safety limits. Incorporating simple interlocking mechanisms into bolted connections significantly reduces on-site labor time and costs, enhancing reusability while maintaining structural capacities. Further analysis indicated that partial interlocking connections are safe for modular buildings of six to eight storeys under wind speeds of 100m/s and for buildings up to 10-storeys under earthquakes with magnitudes up to 5. Additionally, reliability index graphs developed for the connections can be referred to in building design or in developing new intermodular connections.

Ensuring the fire safety of timber structures is important in promoting timber and timber-based construction materials. Among the engineering timber used in the construction, Glue laminated timber (GLT) is a commonly used timber type. Considering timber's anisotropic and heterogeneous nature, it is essential to understand the behaviour of the timber under extreme loading conditions. Developing a numerical model to predict timber behaviour is of importance to designers, considering the cost and time for experimental tests. This study developed and validated a detailed numerical model using Abaqus software with the VUMAT user subroutine. Two models were used for the validation. Charring rates of a non-load-bearing model were studied, while the deflection of a load-bearing beam during fire was analysed. The validated model was then used to predict the residual stiffness of the GLT beam of a 5.2 m span with different numbers of plies. Further, a reliability framework was developed to assess the reliability of timber beams in the event of a fire, and 54 beam samples were numerically analysed. Results show that the number of plies in the GLT beam significantly affects the flexural stiffness when subjected to fire. It was also observed that stiffness reduction with the fire exposure is higher with lesser depths where the GLT beam with 14, 12, 9, 7 and 5 plies have flexural stiffness reduction by 25%, 28%, 29%, 32% and 53%, respectively at the end of the 120 min fire exposure. Moreover, the residual stiffness reduction of the beams of 14 plies with Young's modulus in the 9-13 GPa range is up to 81-76 % during the considered time. Using the reliability framework, a 40 % - 60% reduction in the reliability index of beams was observed due to a nearly 62% increase in span from 3.2 m to 5.2 m for normal conditions and during fire events.

Fire safety is one of the critical concerns for the design and construction of modular structures. The lack of understanding of cavity fire spread in modular construction could create variations in the fire performance of structural members. This study aimed to assess the impact of cavity fire spread in modular buildings initiated by a room fire using validated fire dynamics and structural numerical models. A comprehensive parametric study was conducted to identify critical thermal conditions affecting adjacent structural members under plausible cavity fire scenarios. The identified critical cavity fire thermal conditions were used to examine the structural performance of cold-formed steel intermediate column specimens while varying geometric configurations, material properties, and boundary conditions. The results highlighted two distinct phases of restrained thermal expansion and lateral deformations under material yielding and buckling, resulting in the loss of structural integrity. The restrained thermal expansion significantly increased axial/restraint forces, reaching up to 155% of the initial load. This behavior decreased axial load capacity by 2.4% to 35% of the ambient capacity. Further, the study identifies a requirement for designing the intermediate columns and the connected intermodular connections for increased design action equivalent to 56% of the service load.

Timber modular buildings (TMBs) are increasingly promoted as a low-carbon and resource-efficient solution for modern construction. However, despite growing global interest, the feasibility of applying TMBs, particularly multi-storey systems, remains insufficiently understood in the Australian context. The existing literature largely focuses on isolated aspects, such as structural performance and environmental impacts, leaving a significant gap in system-level evaluations that account for the combined implications of design, durability, fire safety, manufacturing and logistics. This study addresses this gap by reviewing case studies and synthesising the key opportunities and challenges associated with large-scale TMB adoption. The review identifies that while TMBs can deliver substantial environmental benefits and reduced construction time, their widespread deployment is limited by fire safety concerns, long-term durability under Australia’s climate hazards, structural height and span constraints, and logistical limitations associated with transporting modular units. Thus, this study aims to consolidate these specific building design criteria into feasibility assessments and outline targeted potential solutions. These include enhanced encapsulation and cavity-barrier strategies for fire protection, hazard-specific durability detailing, hybrid and lightweight volumetric modules to manage lifting and transport constraints, and performance-based design approaches tailored to the National Construction Code. Overall, the study provides practical recommendations to support the upscaling of multi-storey TMBs in Australia, highlighting where further research, regulatory refinement, and industry innovation are required to overcome current adoption barriers.

Processed sea sand has emerged as a viable alternative to traditional fine aggregates in the Sri Lankan construction industry. Despite its economic and environmental advantages, concerns over residual seashell content have limited its widespread adoption by local contractors. Residual seashell content, typically ranging from 1% to 3% after processing, has raised concerns about its impact on the performance of concrete. This study systematically investigates the influence of seashell fragments, with a content of up to 5%, on the fresh, mechanical, and durability properties of sea sand concrete and mortar. Experimental results indicate that workability remains stable, with minor variations across the tested range of shell content. Compressive strength remains relatively consistent from 0% to 5% seashells, indicating that seashell content does not significantly impact the strength within this range. Durability tests reveal minimal effects of shell content on concrete performance within the tested shell range, as indicated by results for water absorption, rapid chloride penetration, and acid exposure testing. Accelerated corrosion indicates that the typical shell content does not increase corrosion risk; however, high shell content (>3%) can compromise corrosion durability. Overall, these findings demonstrate that the mechanical and durability performance of sea sand concrete remains uncompromised at typical seashell content levels (1–3%), supporting the use of processed sea sand as a sustainable and viable alternative to traditional fine aggregates in Sri Lankan construction.