基于不同预应力度的半刚性节点预压装配式预应力混凝土框架静力弹塑性分析

PUSHOVER ANALYSIS OF THE PRESTRESSED ASSEMBLY PC FRAMEWORK WITH SEMIRIGID JOINTS BASED ON DIFFERENT PARTIAL PRESTRESSING RATIONS

为了解考虑预应力度的节点半刚性对预压装配式预应力混凝土结构地震反应的影响,利用MIDAS/Gen软件建立模型对某7层预压装配式预应力混凝土结构进行静力弹塑性分析,通过改变预应力度大小,研究预压装配式预应力混凝土结构的受力性能、变形能力和框架的耗能机制。理论研究表明:节点半刚性对结构抗力影响很大,预应力筋在延缓结构抗力减小方面发挥了重要作用;在罕遇地震下不同预应力度预应力混凝土结构的层间位移角均能满足设计标准的要求,表明罕遇地震下的结构不产生过大变形;中等预应力度的结构在罕遇地震下,结构塑性铰出现位置除底层柱底外均在梁端,表明可以实现"强柱弱梁"破坏机制,塑性铰位置分布广泛,耗能良好,为整体屈服机制;预应力度较大的预压装配式预应力混凝土结构的抗震性能较好。

In order to understand the influence of different partial prestressing ratios on the seismic response of prestressed assembly PC framework with semirigid joints,MIDAS / Gen software was used to build a model to conduct pushover analysis of a 7-story prestressed assembly PC structure,which could study the mechanical properties,deformation capacity and energy dissipation mechanism of the PC structure by varying the partial prestressing ratios.The theoretical research showed that the semirigid joint had great influence on the structural resistance,and prestressed tendons played an important role in delaying the structural resistance. The PC structure of different partial prestressing ratios could meet the specification requirements in rare earthquake,which showed that the structure under a rare earthquake did not produce excessive deformation. In the rare earthquake,the structure of moderate partial prestressing ratios whose structural plastic hinges positions except the bottom were in the bottom of the column outer end of the beam,showing that it was possible to achieve ＂strong column and weak beam＂failure mechanism,the plastic hinge positions were widely distributed,and the energy consumption was good for the overall yield mechanism. In conclusion,the seismic performance of the prefabricated PC structure with large partial prestressing ratios was better.