桁式组合拱桥施工过程数值模拟

Numerical Simulation of the Construction Process of Trussed Combination Arch Bridge

采用单元死活技术,以贵州省境内的清水大桥为工程背景,对预应力桁式组合拱桥的施工过程进行了数值模拟,以了解成桥过程中的应力、位移变化情况。计算结果显示,该桥体系转换之前力学性能良好,竖向位移较小;体系转换之后局部区域拉应力高于C50混凝土的抗拉极限强度,此为造成该区域产生裂缝的主要原因。

Based on the Qingshui Bridge in Guizhou Province, the method of element＇s birth and death has been adopted for carrying numerical simulation of the construction process of the trussed combination arch bridge. And then, the stress and displacement in the corresponding construction process can be obtained. The results showed that the mechanics performance of the bridge was in good condition and the displacement on vertical direction was small before the structural system was transformed, but the stress in some regions of the bridge was above the tensile strength of the concrete C50 after the structural system was transformed, which may be a key factor on crack occurrence in these regions.