楼板对钢筋砼异形柱框架破坏机制的影响分析

采用基于柔度法的纤维模型梁柱单元，对按现行混凝土异形柱结构技术规程设计的异形柱框架结构，分别按考虑和忽略现浇楼板及其钢筋对梁抗弯能力的增强作用2种情况，分别进行了单向水平罕遇地震输入下的空间结构弹塑性动力分析。对比分析结果表明，现浇楼板及其钢筋将提高框架梁的抗弯能力，从而改变罕遇地震作用下混凝土异形柱结构的破坏模式，对于高烈度区混凝土异形柱结构影响尤为明显，因此该类结构在抗震设计中必须考虑现浇楼板及其钢筋的影响。

Analysis of Failure Mechanism of RC Structures with Specially Shaped Columns Affected by the Diaphragm

With the flexibility-based fiber model, the seismic behaviors of RC structures with specially shaped columns,designed according to the current code, are analyzed under unidirectional rare earthquakes using nonlinear dynamic analysis method. The beam strength is calculated with or without consideration of the diaphragm and its reinforcement. The results are compared and the conclusion has been drawn that the bending capacity of beams would be increased due to the effect of diaphragm and its reinforcement, and which would change the failure mechanism of RC frames under rare earthquake,especially in high intensity areas. Therefore the influence of the diaphragm should be considered during the seismic design of the type of structure.