钢筋混凝土抗震框架节点各机构传递剪力的定量分析

如何正确筛分钢筋混凝土抗震框架节点中两种传力机构,即斜压杆机构和桁架机构在节点不同受力阶段分担的节点剪力份额,是各国研究界在节点传力模型研究中至今未解决的关键问题之一,其核心问题是能否找到一种符合节点受力规律且力学概念清晰的确定这两类机构分担剪力份额的方法。本文在系列试验的基础上,通过对节点传力特征的分析,提出了一种“梁、柱简支杆模型”。利用这一模型可在已知节点周边梁、柱端正截面受力状况的前提下,合理确定梁端为对称配筋或非对称配筋时节点核心区两类传力机构分担的节点剪力份额。对比分析表明,这一方法的计算结果与试验结果符合良好。

Quantitative evaluation of two shear transfer mechanisms in earthquake resistant beam-column joints

It is a very important unresolved problem of how to figure out the contributions of two kinds of shear transfer mechanisms respectively, i.e. the strut mechanism and the truss mechanism, in RC beam column joints subjected to different levels of shear reversals. The main obstacle is to find out a rational method which can not only represent the behavior of joints but also have clear physical background. In this paper, a so called ‘simply supported beam column model’was proposed based on the serial test results. If the forces in the reinforcement and compressed concrete in beams and columns surrounding a joint were known, the contributions of such two mechanisms in shear transfer in the joint core could be determined respectively by using this model, while the upper and lower reinforcement in the beams may be symmetric or asymmetric. The predicted results have shown good agreement with the test results.