STUDY ON SEISMIC PROPERTY OF STEEL COUPLING BEAM WITH RESTRAINED WEB

With constraint plate on both sides of steel web, bearing capacity of Buckling Constraint Steel Coupling Beam can continue to increase after the shear yielding of web under cyclic shear loading. Compared with the traditional way of setting stiffeners on the web, Buckling Constraint Steel Coupling Beam has excellent energy dissipation capacity because the buckling destruction of steel web won't take place until the ultimate shear strain is reached. Five quasi-static tests on Buckling Constraint Steel Coupling Beam were carried out to study the impact of various constraint manners on seismic behavior of this type of steel coupling beam. Test results indicate that all the test specimens undergo shear yielding and achieve the increasing of bearing capacity, followed by two types of failure modes, i. e., constraint plate bending failure and fracture at the weld connecting link flange to end plate. The average over-strength factor of all specimens reaches 1.38, higher than the value of 1.1 required by GB 50011-2010. Specimens with 50 mm thick concrete constraint plate and 25 mm thick wooden constraint plate both have an over-strength factor larger than 1.5. Based on finite element analysis, the comparison between test results and parametric analysis was conducted, and the minimum thickness of constraint plate was proposed for practical design.