摘要:
我国目前采用的"三水准、两阶段"的抗震设计方法允许结构在地震作用下发生塑性变形,但因地震的复杂性与不确定性,导致结构、构件产生较大残余变形,造成震后修复困难或无法修复的情况。因此,采用直接基于位移的抗震设计方法求解地震作用并对自复位框架进行设计,对结构进行动力弹塑性时程分析。结果表明:当计算配筋后,重新计算结构整体的自复位比,并用新的自复位比得到计算的结构基底剪力VBase与设计基底剪力相差不到1%,说明该设计方法具备良好拟合性;动力时程分析表明结构的顶点位移响应可以看出结构整体较为稳定,说明结构处于完好状态,没有发生倒塌破坏,满足罕遇地震下抗震设防要求,并且结构的抗震性能比现浇节点更优异。
Abstract:
The "three levels and two stages" seismic design method currently adopted in China allows structures to undergo plastic deformation under the action of earthquake. However, due to the complexity and uncertainty of earthquakes, structures and components have large residual deformation, which makes it difficult or impossible to repair after the earthquake. Therefore, the displacement-based seismic design method was adopted to calculate the earthquake force and design the self-centering frame, and the dynamic elastic-plastic time-history analysis of the structure was carried out. The results showed that when the self-centering frame joint design was completed, the self-centering ratio and the base shear VBase of the whole structure were recalculated, which was less than 1% from the design base shear force, indicating that the design method had a good fit; according to the results of dynamic time-history analysis, it could be seen that the overall seismic performance of the structure was good, and there was no collapse damage, which could meet the seismic fortification requirements under rarely occurred earthquakes, and the seismic performance of the structure was better than that of cast-in-place joints.