Seawater-sea sand concrete has emerged as an innovative construction material due to its effective utilization of marine resources. At the same time, geopolymer concrete has shown rapid hardening capabilities, low energy consumption, and eco-friendly properties, making it highly promising for structural reinforcement. This study evaluated the effects of alkali modulus, alkali concentration, and fly ash (FA) content on the performance of geopolymer FA-slag seawater-sea sand mortar (SWSSGM). Performance characteristics such as consistency, flowability, compressive strength, and flexural strength were tested. The findings indicate that FA enhances workability, whereas slag powder has the opposite effect. Increasing alkali concentration reduces consistency but increases slump. Optimal compressive and flexural strength is achieved when the alkali modulus is 1.2, alkali content is 15%, and FA content is 30%. Generally, higher alkali concentrations promote strength development, while increased FA content raises porosity and reduces strength. However, strength gains over time are more pronounced, and the effects of alkali modulus require further investigation. Multiple linear regression analysis of the three factors affecting SWSSGM properties demonstrates that a quadratic polynomial regression model yields high coefficients of determination (R² ≥ 0.92), enabling accurate predictions of SWSSGM performance parameters. From a lifecycle (cradle-to-gate) perspective, SWSSGM outperforms traditional cement-based materials in terms of carbon emissions, energy consumption, and resource efficiency, showcasing its significant low-carbon, energy-saving, and environmentally friendly attributes. Through systematic optimization of SWSSGM’s design parameters, performance prediction modeling, and preliminary environmental assessment, this study provides guidance for its sustainable application in coastal engineering projects.

The increasing digitalization of the construction industry is reshaping how professionals are trained and educated. As a key component of construction education, traditional site visits provide students with valuable first-hand exposure to real-world construction environments. However, despite their educational value, such visits present multiple challenges, including scheduling difficulties, limited site capacity, health and safety restrictions, induction requirements, and high logistical costs. In recent years, Virtual Reality (VR) has offered new opportunities to deliver remote, realistic, and interactive site experiences that replicate the authenticity of on-site learning without requiring physical presence. Previous studies have primarily focused on fully computer-generated VR environments developed using platforms such as Unity or Unreal Engine. While these models offer flexibility and interactivity, they often lack the contextual realism of actual construction sites. Addressing this gap, the present study designed and developed a VR immersive construction site experience tailored to the Australian construction industry, built from 111 high-resolution 360° panoramas captured at a real construction site. The system architecture was developed using an incremental development approach to manage complexity, refine functions, and ensure continuous feedback. Drawing on insights from a systematic literature review, the system architecture specifically targeted barriers to VR adoption in construction education. The resulting prototype was evaluated by 31 students, revealing positive perceptions across all key constructs, with mean scores of 4.31 for usefulness, 4.30 for ease of use, and 4.28 for learning impact (five-point Likert scale). This study represents a pioneer exploration in establishing a scalable and educationally aligned framework for VR-based construction learning. Future development stages will focus on expanding the system to cover diverse project types, integrating adaptive learning features, and linking it with learning management systems to enhance engagement and learning analytics.

Integrating Carbon Capture, Utilization, and Storage technology into concrete additive manufacturing represents an innovative pathway for achieving carbon emission reduction in the construction industry, while simultaneously offering effective solutions to critical challenges such as insufficient early-age strength and weak interlayer bonding in printed components. Bibliometric analysis reveals that this interdisciplinary field is experiencing a period of exponential growth, with research hotspots rapidly shifting from fundamental 3D printing process exploration to the synergistic optimization of material properties utilizing accelerated carbonation and carbon dioxide sequestration technologies. This review systematically elucidates the mechanisms of carbon mineralization curing, with a particular focus on analyzing three key process pathways: fresh state carbon mineralization, synchronous carbon sequestration during printing, and post-printing carbonation curing. Furthermore, the synergistic enhancement mechanisms of material strategies, including supplementary cementitious materials and carbonated recycled aggregates, are discussed. On this basis, the review identifies core challenges regarding curing uniformity, narrow process windows, and the absence of long-term durability research, and subsequently outlines future development directions such as intelligent closed-loop control and integrated structure-material-process design.

Against the backdrop of global climate anomalies and rapid urbanization, rainfall-induced urban flooding has become increasingly frequent. Wuxi, a city in southern Jiangsu Province, suffers annual casualties and economic losses due to flooding, leading to urban chaos. This study proposes a quantitative evaluation of the level of urban flood resilience using a system of resilience evaluation indicators. An evaluation indicator system for urban flood resilience encompassing infrastructure, environment, society, and economy was constructed with 26 indicators. A hybrid multi-criteria decision-making method integrating the Analytic Hierarchy Process, entropy weight method, and GIS technology was developed to assess flood resilience in Wuxi systematically. Additionally, emergy analysis was applied to evaluate urban sustainability. The results indicate that five administrative districts centered in Liangxi District and parts of Yixing City near water bodies exhibit low resilience due to gentle slopes, proximity to active river channels, and high population density. In contrast, most areas of Jiangyin City demonstrate higher resilience owing to elevated terrain, fewer social vulnerabilities, and advanced economic development. The model’s consistency was validated using the Area Under the Curve (AUC) method, yielding an AUC of 0.843. The Emergy Sustainability Index for Wuxi was 0.08 < 1, indicating an unsustainable state. This study provides actionable recommendations for enhancing urban flood management and regional resilience.

Solid waste generation from industrial production and construction activities has increased sharply in recent years. Improper disposal and abandonment of solid waste have led to significant resource loss and pose serious risks to soil, water, and air quality. As a result, incorporating solid waste into concrete production presents a promising strategy to reduce environmental pressure and promote sustainable development. This review investigates the feasibility and performance of various solid waste materials, such as fly ash, limestone powder, stone sludge, silica fume, waste glass, rubber particles, and recycled concrete sand, that are incorporated into 3D printed concrete (3DPC). These materials demonstrate the potential to enhance rheological behavior, mechanical strength, interfacial bonding, and dimensional stability of printable composites. Additionally, their incorporation reduces carbon emissions, diverts waste from landfills, and promotes resource circularity. The benefits and limitations of solid waste are critically evaluated, including printability challenges arising from particle morphology and water absorption. The review emphasizes the need for standardized cost-effectiveness analysis frameworks to quantify economic and environmental balance. Finally, this study highlights the importance of optimizing mix design, surface treatment techniques, and large-scale production strategies to enable widespread adoption of waste-based 3DPC in sustainable construction.