采用装配式滑支板式楼梯的RC框架结构抗震性能

Seismic performance of RC frame structures with prefabricated slab stairs

基于ABAQUS对楼梯建立有限元模型,通过与试验楼梯的对比验证数值模型的适用性;用该基础模型分别对采用现浇抗式板式楼梯和装配式滑动支撑板式楼梯的钢筋混凝土(RC)高层框架结构模型进行时程分析,从位移响应、塑性损伤发展及地震响应的角度研究各方式对结构抗震性能的影响,比较了多高层结构滑支楼梯的抗震性能。结果表明:带现浇抗式连接楼梯的框架结构位移响应大,扭转效应加剧,应力更加集中,地震作用增大,结构损伤严重,更易发生受拉及受压破坏;带装配式滑动支座楼梯的框架结构位移较小,应力分布较均匀,构件损伤较小,能作为安全通道在震后得以保留,在位移响应、应力损伤及地震响应多方面的效果均优于带现浇抗式连接的框架结构;带滑动支座的高层相较于多层在整体应力、塑性发展、损伤范围及程度上均更严重,滑动效果表现更好。

The numerical analysis results of staircase, based on the finite element software of ABAQUS, are compared with the experimental results to verify the applicability of finite element parameters and modeling method. On this basis, 2 groups of reinforced concrete(RC) high-rise frame models are established to perform dynamic time-history analysis in two circumstances:the adoption of cast-in-place resistant connection and that of prefabricated slip connection. Multiple aspects are adopted to research the influence of each modeling method on structural seismic performance, including the displacement response, the plastic damage evolution and the seismic response. And the seismic performance of multi-storey and high-rise models are compared. The analysis results are as follows. Cast-in-place resistant connection causes larger displacement, aggravates the torsion effect, causes severe stress concentration and amplifies the seismic effect, which ultimately leads to seriously structural damage and tension or compression failure. Prefabricated slip connection has smaller displacement, more homogeneous stress distribution and slighter damage of members, which can ensure that the stairways are reserved as safe passage after an earthquake;therefore, prefabricated slip connection performs better in terms of the displacement response, the stress damage and the seismic response than cast-in-place resistant connection. Compared with multi-storey model, the high-rise model has more severe seismic results in the whole stress, plastic development, damage range and severity, which makes it behave better in slip effects.