Experimental study on seismic performance of prefabricated grid composite walls with different vertical connection forms

This experimental study evaluates the seismic performance of two vertical connection types in a novel precast grid composite wall structure (PGCWS): a steel bar anchorage (SW-1) and a mortar cushion connection (SW-2). Quasi-static cyclic tests were conducted on 1:2-scale specimens to assess failure modes, hysteretic behavior, stiffness degradation, and energy dissipation capacity. The results indicate that SW-1 maintains structural integrity and facilitates controlled damage distribution, demonstrating ductile failure with an ultimate drift of 1/45.5, stable hysteresis loops, and high energy dissipation (20,400 kN mm). In contrast, SW-2 exhibited premature interface slip, resulting in brittle failure characterized by significant hysteresis pinching, rapid stiffness loss, and substantially lower energy dissipation (11,400 kN mm), with a limited ultimate drift of 1/66.5. Based on these findings, performance-based design recommendations are proposed. The steel bar anchorage is advised for mid- to high-rise buildings in high-seismic regions due to its robustness and energy dissipation capability. The mortar cushion connection may be suitable for low- to mid-rise structures where construction efficiency is emphasized, provided that inter-story drift is strictly controlled. This research offers essential experimental evidence to support the practical implementation of PGCWS.