To address complex connections in prefabricated concrete structures, a novel joint connecting a prefabricated concrete-filled steel tubular column and a composite beam is proposed. Pseudo-static tests on six scaled specimens and ABAQUS finite element analyses were conducted to investigate seismic mechanisms, focusing on slab effects and beam-bottom configurations. Experimental results show the joints exhibit plump hysteretic curves. The composite beams displayed distinct shear-dominated failure, while the stiffened column remained intact. With an average ductility coefficient of 2.84 and an ultimate equivalent viscous damping coefficient of 0.207, the specimens demonstrated excellent deformation and energy dissipation capabilities. The slab’s flange effect significantly enhanced negative bearing capacity, causing mechanical asymmetry. Comparatively, the steel plate beam bottom configuration offered superior stiffness and stability over the reinforcement beam bottom configuration. Sensitivity analysis revealed that bearing capacity is highly sensitive to beam parameters (e.g., longitudinal rebar strength, connector length) but less sensitive to column parameters. Notably, the bearing capacity of the beam bottom configuration using reinforcement increases significantly with concrete strength and reinforcement ratio, whereas the beam bottom configuration using a steel plate shows marked insensitivity to these factors. These findings clarify the load transfer mechanism and support the seismic design of prefabricated structures.

The energy-saving performance of the building envelope, which plays a pivotal role in energy conservation and thermal insulation, has been the subject of extensive research. In the context of China’s high-quality green development, this study proposes a building energy-saving strategy based on optimal thermal comfort. It analyzes the impact of factors such as regional dwell time and PMV types on energy-saving effects, summarizes the optimal comfort parameters under the highest energy efficiency rate, and sets relevant parameters in the DeST building energy simulation software to analyze a typical public building. The analysis examined the impact of changing the heat transfer coefficients of exterior walls and windows on the annual cumulative heating and cooling loads. It established the relationship between the thermal transmittance of building envelopes and energy consumption and assessed the carbon emissions during the building’s operation and maintenance phase. The results indicate that as building envelope thermal transmittance coefficient decreases, particularly that of external windows and walls, overall cumulative heating and cooling loads decline accordingly. Notably, the reduction in external windows’ thermal transmittance coefficient has the most significant impact on total building thermal load. Furthermore, as the envelope thermal transmittance coefficient decreases, seasonal heating and cooling demands decline simultaneously, with the most substantial effect on heating load reduction during winter. Total annual building carbon emissions also decrease with the reduction in envelope thermal transmittance coefficient, particularly external wall thermal transmittance coefficient. Based on the findings of this study, the building envelope of the public building was redesigned, taking into account construction costs, the owner’s requirements, and energy efficiency alongside the reduction in carbon emissions. Comparisons of the redesigned building’s envelope thermal performance, experimental testing, and in situ measurements confirmed that it fulfilled the engineering requirements. This study also demonstrates that DeST software provides reliable technological support for low-carbon building design, retrofitting, and operation.

To thoroughly investigate the anchorage performance of a novel prefabricated concrete shear wall system assembled by anchoring closed-loop rebar, rebar pull-out tests were conducted. The effects of different rebar distribution forms, closed-loop rebar anchoring heights, and dowel rebar diameters on anchorage performance were considered. Strain measurements at key points were taken, and the failure modes and peak loads of shear walls with various closed-loop rebar assemblies were obtained. The results indicated that the rebars in all specimens fractured, with peak loads ranging from 90 kN to 100 kN, satisfying the anchorage requirements of the rebar. This demonstrates that even when the anchorage length of the rebar is less than specified, the method of assembling by anchoring closed-loop rebar can still provide good anchorage performance. Moreover, steel bars and concrete have different damage and failure characteristics under different load levels. This research also indicates that specimens with uniformly distributed closed-loop rebar exhibit superior anchorage performance compared to those with adjacent distribution. Furthermore, increasing the overlapping height of the closed-loop rebar contributed to enhancing the safety margin of the anchorage, while the diameter of the dowel rebar (similar to stirrups) had a relatively minor effect on the anchorage performance. These findings provide a scientific basis for the design and construction of prefabricated concrete shear walls with closed-loop rebar.

Non-point source fugitive dust produced during municipal road construction is one of the main ambient air pollutants gravely threatening the life and health of construction workers and residents around construction areas. In this study, a gas-solid two-phase flow model is used to simulate the diffusion behavior of non-point source dust with different enclosure heights under wind loads. Moreover, the inhibitory effect of the enclosure on the diffusion of non-point source dust from construction to residential areas is analyzed. The results show that the physical blocking and reflux effects of the enclosure can effectively restrain dust diffusion. When the enclosure height is 3–3.5 m, the concentration of particulate matter in most sections of residential areas can be reduced to less than 40 μg/m³. Moreover, when the wind speed is 1–5 m/s and the enclosure height is 2–3.5 m, the diffusion height of non-point source dust particles above the enclosure is concentrated in the range 1.5–2 m. This study provides a scientific basis for setting the heights of enclosures and atomization sprinklers at construction sites. Further, effective measures are proposed to reduce the impact of non-point source dust on the air environment of residential areas and health of residents.