Experimental Study on Seismic Performance of Composite Coal Gangue Concrete Prefabricated Grid Wall

To address the synergistic challenges of construction efficiency and seismic performance in traditional prefabricated shear wall structures, this study proposes a composite coal gangue concrete prefabricated grid wall system. Low-cycle reversed loading tests were conducted on three half-scale coal gangue grid wall specimens to systematically investigate the effects of grid configurations on failure mechanisms and seismic performance. Experimental results demonstrated that all specimens exhibited flexural-shear failure modes with symmetric hysteretic and skeleton curves. The failure sequences of specimens GGSW-2 and GGSW-4 followed a multi-defense-line seismic mechanism, progressing from non-reinforced concrete zones to confined grid elements and finally to edge-constrained components. Among them, GGSW-2 achieved the highest load-bearing capacity, optimal ductility, and superior energy dissipation performance. While GGSW-4 exhibited reduced load-bearing capacity, its lightweight characteristics and thermal insulation advantages make it suitable for low- to mid-rise buildings. In contrast, GGSW-5 experienced brittle failure due to stress concentration at the base joint, necessitating optimization of vertical joint details to enhance ductility. The tests revealed the constraint effect of the grid system on crack propagation, validating the functional zoning design philosophy of the prefabricated coal gangue grid wall system. This study provides theoretical insights for improving seismic performance and functional differentiation in prefabricated structures.