摩擦耗能部分自复位连接组合框架边节点抗震性能试验研究

To further investigate the seismic performance of the exterior joint with partial self-centering friction damped connection in innovative PEC column-steel beam composite frame,axial compression of PEC column and its layout was taken into consideration to design three 1∶1.6 scale specimens and then tests were conducted under quasi-static cyclic lateral loading.Based on test measurements and observation,the specimens' seismic performances were studied,including the load-carrying capacity,bending stiffness degradation,residual drift angle,hysteretic energy-dissipation and load-carrying mechanism of joint.The results showed that post-tensioned bars provided restoring force to realize self-centering function and friction energy-dissipation plates can provide energy dissipation capacity to reduce the structural earthquake response.Axial compression of PEC column increased the initial bending stiffness but its second effect accelerated the energy-dissipation developing process,while the layout of PEC column had little effect on initial flexural stiffness and developing process of flexural stiffness degradation and energy-dissipation.The specimen SMJ-2 exhibited superior self-centering function as its residual drift angle was less than 0.005 rad when test end with the loading drift 3.18%,the specimen SMJ-3 owned sound self-centering function as its residual drift angle was less than 0.005 rad when the loading drift approximately equaled to the inter-story drift limit (1/50) at design based earthquake level and 0.01 rad when the loading drift surpassed the inter-story drift limit (1/30) at maximum considered earthquake level,while the residual drift angle of specimen SMJ-1 was less than 0.01 rad when loading to the inter-story drift limit (1/50) at design based earthquake level,but it was increased with the second-effect of axial compression of PEC column,which led to the decay of its self-centering function.