Experimental study of flexural critical reinforced concrete filled composite plate shear walls

The reinforced concrete filled composite plate shear walls (CPSW) system employs two steel plates with infilled reinforced concrete. Based on an experimental study of four flexural critical CPSW specimens under high axial compression ratio ranging from 0.313 to 0.542 and reciprocal lateral load, the seismic performance of shear studs connected CPSW systems with orthogonal reinforcement in wall web and longitudinal reinforcement in boundary element is examined. The failure mode, load-displacement relationship, flexural strength, displacement capacity, stiffness degradation and equivalent damping ratio are reported in detail. The compression yielding of boundary element was observed before its local buckling, and yielding of faceplate was observed before faceplate local buckling. The fracture failure of the boundary element and crushing of infilled concrete were observed at the descending branch. The test results showed that the CPSW systems connected by shear studs had adequate ductility, and the ultimate drift ratio ranged from 1.17% to 1.78%. The overstrength ratio of the moment capacity ranged from 1.06 to 1.18 in the test. Based on the plasticity theory, the strain measurement results of steel faceplates were used to calculate the shear force contribution of the steel plate. The influence of axial compression ratio on the internal force transfer and ultimate capacity is investigated. In addition, a database of 47 flexural critical CPSW specimens with boundary element was established, and the overstrength ratio for the anchorage design was proposed with adequate safety.