Experimental Study On Seismic Behavior Of Replaceable Steel Beams In Assembled RCS Hybrid Structures

An replaceable steel beam which can be used in RCS hybrid structure was proposed.It includes replaceable fuse and two irreplaceable parts.Cyclic loading tests were performed.The result show that:(1)The damage of all specimens concentrated on the replaceable fuse.Two irreplaceable parts were still elastic at the end of test.It proved that the proposed beam was reasonable.(2)The replaceable beam had good plastic-deformation and energy-dissipation capacity.The plastic drift of all specimens exceeded 0.03 rad which can meet the requirement of AISC.(3)The load and deformation capacity of steel beam replaced after damaged were almost at the same level as the corresponding specimen before 1/30 story drift.It showed that the proposed beam was earthquake-resilient.(4)The proposed beam which could be replaced easily after each test was replaceable.(5)The overstrength coefficient of bearing capability Cpr has a big influence on strength-matching relationship of replaceable and irreplaceable part and the final failure mechanism.Based on this test result,the recommended value of Cpr is 1.1-1.2.(6)Although the proposed beam was damage-controlled and replaceable,there were severe residual deformation during the late loading stage as result of the plastic deformation of fuse.So the design should be innovated to reduce the residual deformation.Nonlinear numerical simulation under cyclic loading on the replaceable steel beam was carried out by ABAQUS program,showing good agreement with the test results.