An Experimental Study on Seismic Performance of Steel Truss Coupling Beams with Buckling-restrained Brace

Through the pseudo-static test on the steel truss coupling beams with buckling-restrained brace, the bearing capacity, deformation capacity, hysteresis curve, skeleton curve, ductility, Energy Dissipation and stiffness degradation of such coupling beam are understood. The test results show that the steel truss coupling beams with buckling-restrained brace is characterized by bigger bearing capacity, higher ductility and good plastic energy dissipation capacity. 1. PREFACE Characterized by high stiffness and strong lateral resistant ability, the concrete shear wall is widely used in the high-rise building construction system, among which, the hybrid coupled wall is the most typical and widely used shear wall. In the concrete coupled shear wall, the coupling beam is the key component that affects the seismic performance of shear wall structure. Under the action of small seisms, the coupling beam should provide the coupling wall column with the stronger binding effect, strengthen the lateral stiffness, reduce the lateral deformation and increase the bearing capacity of the structure; when the rare earthquake occurs, the coupling beam should yield before the coupling wall column so as to consume the earthquake energy and weaken the seismic response through the plastic deformation of the coupling beam (1). The concrete coupling beam has some common shortcomings, including heavy self- weight, low bearing capacity, insufficient ductility, limited energy dissipation capacity and difficult post-earthquake reconstruction (1). In recent years, some foreign scholars propose to use the solid-web steel coupling beam to replace the concrete coupling beam; the test and theoretical research results show that the steel coupling beam designed rationally is equipped with sufficient strength, stiffness and toughness and the hybrid coupled wall construction system composed by steel coupling beam and concrete coupling wall column has good seismic performance. Through applying the steel coupling beam, the complex reinforcement and structural measures of concrete coupling beam can be avoided, the construction difficulty and cost can be reduced and the structure can be repaired and changed after disaster (2). Some developed countries, including America and Canada, have launched the corresponding design codes and suggestions (3).