【摘要】 首先对2种基于纤维截面的弹塑性梁单元,即沿单元长度积分的纤维弹塑性梁单元和基于子单元法建立的带长度的纤维塑性铰弹塑性梁单元的本构特征进行了分析,然后以地震作用下一桥梁工程为例,从静力和动力2个方面对比了这2种单元的主要非线性特性.结果表明:前者可以模拟受力过程中沿单元长度方向截面刚度的连续变化,后者则可以体现双线性特征;带长度的纤维塑性铰弹塑性梁单元是对纤维弹塑性梁单元的一种较好的近似,但在动力分析中,如果有未屈服构件的显著影响,则会出现相对略大的差异.更多还原

【Abstract】 The constitutive features of two elastoplastic beam-column elements with fiber sections were analyzed,that is,the fiber elastoplastic beam-column element based on the integration along element length,and the elastoplastic beam-column element with fiber plastic hinges with specific length based on the element method. The nonlinear static and dynamic characteristics of the two elements were compared based on an example of a bridge under earthquake. The results show that the former may simulate continuous variation of sectional stiffness along the element length under stress conditions,and the latter may exhibit bilinear characteristics. The beam-column element with fiber plastic hinges with specific length is a satisfactory approximation to the fiber elastoplastic beam-column element. If there exist significant influences of unyielding components,relatively notable difference will occur in seismic analysis.更多还原