| Coupling beams are important energy dissipation components of the shear wall strutures,the stiffness is very big but shear failure would easily take place in the small ratio of span-depth RC coupling beams,so that these coupling beams can not satisfy the requirements for better ductility and energy dissipation capacity.The steel truss coupling beams which possess good seismic performance,this paper studied,could meet the stiffness requirement in different stages of the high-rise building structures,and have important applications in structural energy dissipation and play the role of a passive control characteristics of the structure.In this paper,4 coupling beams which the ratio of span-depth is 1.0 and 1.25,2 with friction control joint and 2 with similar form of ordinary steel truss coupling beams,were tested under cylic reversed loading.Based on the results,we know that mainly by means of the crosswise rods and chords,plastic deformation,ordinary steel truss coupling beams possess high strength、stiffness and good ductility;Mainly by means of the friction joint for sliding and the deformation of chords,the steel truss coupling beams with friction joint have better ductility and energy dissipation capacity,hysteretic loops of load-deflection of them are very good.The stiffness is big,after friction joint slided,stiffness turns down but it can repair easily,so that we can realize the control concept for dissipation and damping which is "big stiffness under frequent earthquake and small stiffness under major earthquake”.Although there are several obviours cracks in bearing node of coupling beams,the undamaged node agree with the test result.Then we test the strain of the control point to study the coupling beams of the mechanism of force,and analyze how the design parameters influence the behavior of strength,stiffness,deformation,dissipation of these specimens.Finally,the paper point out the further studies on specimen parameters,design of friction node and theoretical analysis. |
