徐变对钢管混凝土拱桥拱肋截面应力重分布的影响

Analysis of Cross-section Stress Redistribution in CFST Arch Bridge under the Standing Load

采用混凝土徐变理论及有限单元法 ,并考虑混凝土的弹性后效及混凝土受四周约束作用的徐变特性 ,对任意形状拱肋截面的钢管混凝土拱桥的应力重分布进行研究 ,推出短期荷载作用下截面应力和在长期荷载作用下应力重分布的半解析表达式 ,提出相应的分析方法及实施步骤。分析表明 ,徐变对钢管混凝土拱桥的截面应力重分布影响非常显著 ,如与外荷截作用下的应力相叠加 。

The concrete creep theory and the finite element method are used, in consideration of the elastic post effect of concrete and creep features of concrete restrained all around, to analyze stress redistribution of steel tube concrete(CFST) arch bridge with arbitrary shape cross section. Stress under short term loading and stress redistribution under standing load have been developed and the procedure for the analysis is also presented. The analysis results show that the creep has a great influence upon the cross section stress redistribution of CFST arch bridge. If the creep is superposed on the stress resulted from external loading, the performance of structural member and component may deteriorate.