钢筋混凝土桥墩的二阶效应影响研究

Research on Reinforced Concrete Pier Second-Order Effect

本文扼要介绍了钢筋混凝土桥墩二阶效应计算方法的发展及应用。相对于仅适用于简单结构的偏心距增大系数法,基于构件折减刚度的弹性有限元法,采用折减系数考虑非线性的影响,具有更广泛的适用性。针对该弹性有限元法,本文进一步对比了中美混凝土设计规范中折减系数的不同取值。在数值算例中,用三种不同方法分别计算了二阶效应对单墩墩底弯矩的影响,计算结果表明偏心距增大系数法的计算结果偏于保守。

The development and application of reinforced concrete pier second-order effect calculation method have been introduced in this paper. Compared with the law of the change of moment merely implied on simple structures, the elastic finite element method, based on reduced rigidity and using reduction factor to consider the no-linear effect, has an extensive applicability. As for the elastic finite element method, this paper compared the different values of reduction factors in the concrete design code of China and the United States. In numerical examples, three methods are applied to calculate the influence of second-order effect on the moment at the bottom of single pier. The results show that the law of the change of moment is conservative.