Seismic performance of truss-wall joints in high-rise connected structures

Abstract

This paper presents an experimental study of the seismic behavior of joint between steel-truss viaduct and reinforced concrete (RC) seismic walls in connected structures. To investigate the seismic performance of the connection joints, two types of joints with different details (i.e., a common connection joint and a friction energy-dissipation connection joint) were prepared and quasi-statically tested using a cyclic loading protocol. Diagonal concrete cracks in the RC seismic wall, concrete crushing, and the fracture of the weld at the upper chord joint were observed during the test. Unexpected plastic deformation occurred in the embedded chord within the RC seismic wall. The seismic performance of the joints was evaluated in terms of strength degradation, rigidity degradation, ductility, and energy dissipation capacity. The deformation capacity and energy dissipation capacity of specimen CWTJ2 was better than that of CWTJ1. The yield displacements Δy of both specimens were similar. However, the ultimate displacement Δu of CWTJ2 was 34.9% larger than that of CWTJ1, and the accumulated energy Ea of CWTJ2 was 2.23 times of CWTJ1. The load transfer mechanism analysis based on the stress distribution indicates that the embedded column and chords transmitted the load to the seismic wall, which caused the seismic wall to be damaged during the loading process. The experimental results suggest that the truss-wall joints in connected structures can transfer seismic loads effectively. However, the welding between embedded column and chord shall be carefully treated.