【摘要】 针对预应力混凝土(PC)框架节点抗剪强度合理计算模型的缺乏,建立了一个显式考虑预应力效应的改进拉压杆模型。依据Kupfer-Gerstle双向拉压强度准则,考虑了节点核心区混凝土软化效应,并基于此准则推导了一个简便实用的受剪承载力预测公式。通过对文献中21组内、外节点进行分析,得到试验值与模型预测结果的平均比值为1.14,离散系数为0.139,表明本文公式预测结果较精确、连续且偏于安全,而且还优于《混凝土结构设计规范》(GB 50010—2010)中的设计方法,可用于有、无粘结PC框架节点的抗震设计。更多还原

【Abstract】 Due to the scarcity of rational models for predicting the shear strength of prestressed concrete(PC) beam-column joints,a modified strut-and-tie model was established.In the proposed model,the effect of prestress was explicitly taken into account.Kupfer-Gerstle biaxial tension-compression failure criterion of concrete was utilized to take account of the concrete softening effect,based on which a simple and convenient formula was derived.A comparison of 21 exterior and interior beam-column joints shows that the model predictions were accurate,consistent and conservative with an overall average test result to prediction of 1.14 and a coefficient of variation of 0.139,and also illustrate its superior accuracy over the design method of Code for design of concrete structures(GB 50010—2010).It indicates that the proposed model can be employed for design of PC beam-column joints with bonded and unbonded tendons.更多还原