Current Issue : July-September Volume : 2026 Issue Number : 3 Articles : 5 Articles
This study evaluates the energy-saving potential of hollow glass windows integrated with reflective aluminum foil louvers, tailored for hot-summer, cold-winter regions. The reflective integration minimizes solar absorption and bolsters insulation. Experimental results indicate a 14.9% reduction in heat transfer coefficient (K) (from 2.427 to 2.066 W/[m2·K]) and a 20% decrease in shading coefficient (SC) (from 0.30 to 0.24) compared to standard louvers in the closed position. Furthermore, a coupled effect between air layer thickness (δ) and louver angle (θ) on K is observed, with smaller δ intensifying θ’s influence. The reflective system demonstrates superior thermal performance at a modest cost increase of 3.4%, rendering it viable for energy-efficient applications....
The aseismic capability of a beam-to-column connection may be lower under identical bidirectional compared to unidirectional loads. However, earthquake excitations are multidimensional and random, so joints may be simultaneously subjected to different biaxial loading. The aseismic capability and mechanisms of the joints in reinforced concrete (RC) frame structures subjected to different biaxial loading have not been evaluated in detail. This work obtains the combined shear deformation of joints by testing RC frame joints subjected to biaxial cyclic loading and analyzes the shear transfer mechanism and the seismic performance of the joints, respectively, under the same and different bidirectional reciprocated loads. Compared to the spatial joints in RC frame under unidirectional extrude, the shear strength decreased by 21%–29% in the joints subjected to biaxial loading. Moreover, the aseismic capability of beam-to-column connections in RC frame subjected to different bidirectional loads is defined. Finally, the criterion of “strong joint and weak component” is improved....
Right now, there are limited studies on how concrete soil resists sulfate when an electric field and fly ash are used together, and the theory behind stray current engineering protection is not fully developed. This study looks at concrete mixed with fly ash when an electric field is applied. It investigates how well it can resist damage from sulfate and helps explain how its strength and tiny structure change, aiming to fill a gap in current research. The effect of fly ash mortar on the sulfate resistance of concrete and its microscopic mechanism were studied. In this study, the water–cement ratio (W/C) was 0.3, 0.4, and 0.5, respectively, the content of fly ash varied at 0%, 20%, and 40%, and the soaking mode was full-immersion and semi-immersion. The age was divided into 14 days and 28 days to research the effects of fly ash content, W/C, age, and soaking method on the mechanical properties and microstructure of concrete mixed with FAM against sulfate erosion. The results show that incorporating 20% fly ash optimizes both compressive strength and sulfate erosion resistance, while higher contents (e.g., 40%) reduce durability. A lower W/C (0.3) enhances compressive strength but slightly reduces sulfate erosion resistance. Electric field curing moderately improves sulfate erosion resistance, with the highest sulfate erosion resistance observed at 14 days. These highlight the significance of optimizing fly ash and curing conditions to progress the durability of concrete in sulfate-rich situations, subsequently advancing the feasible utilization of green building materials. Its long-term durability under field conditions needs to be further studied. This research provides a new idea for improving the durability of fly ash concrete in sulfate environment and promotes the sustainable development of green building materials....
Solidification/stabilization (S/S) is a widely adopted remediation technique for contaminated soils. However, how to efficiently and economically modify contaminated soil remains challenging. In this study, secondary aluminum ash slag (AAS) was employed as a novel stabilizer for the S/S treatment of lead (Pb) and zinc (Zn) contaminated soils. Two sample preparation methods (internal/external addition) were compared via unconfined compressive strength (UCS) and hydraulic conductivity tests. Toxicity characteristic leaching procedure (TCLP) tests were further conducted to evaluate the retention capacity of contaminated ions. Hereafter, microstructural characterizations, including scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS) and mercury intrusion porosimetry (MIP) analyses, were performed to elucidate the stabilization mechanisms. Results show that moderate incorporation of AAS can significantly enhance both mechanical and stability behaviors. An optimal AAS dosage of 4% achieved a UCS exceeding 2000 kPa; the hydraulic conductivity and leaching concentration were also improved. Microstructural analysis indicated that external addition of AAS promoted the formation of calcium aluminosilicate hydrate (C-A-S-H) and ettringite (AFt), enhancing compactness through pore filling. These findings demonstrate the potential of AAS as a sustainable and cost-effective stabilizer for S/S treatment of contaminated soil....
The Saudi construction industry relies heavily on a multinational workforce, raising safety concerns under high productivity demands. Although productivity pressure is widely assumed to influence workers’ risk perception and unsafe behavior, empirical evidence directly testing this assumption in culturally diverse construction settings remains limited. This study examines whether perceived productivity pressure predicts risk perception among construction workers from different national backgrounds working on the same project. Survey data were collected from 247 construction workers representing five nationalities on a university construction site in Saudi Arabia. Correlation analysis, regression modeling, and linear mixed-effects models were used to assess the relationship between productivity pressure and risk perception while controlling for age and nationality. The results show that perceived productivity pressure does not significantly influence workers’ risk perception, and this relationship is not moderated by age or nationality. Although cultural adjustment differed significantly across national groups, nationality did not alter the pressure risk perception relationship. These findings challenge prevailing assumptions in construction safety research and suggest that productivity pressure may affect unsafe behavior through mechanisms other than cognitive risk appraisal. The study contributes empirical evidence from a controlled multicultural setting and highlights the need for safety interventions that extend beyond productivity pressure management to address decision-making processes, communication, and risk assessment competencies within multinational construction workforces....
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