斜拉-自锚式悬索组合体系桥梁结构参数变化对活荷载效应影响

Influence of Change of Structure Parameters of Cable-stayed and Self-anchored Suspension Combination Bridge on Live Load Effect

基于线性二阶和非线性理论对一座多塔斜拉-自锚式悬索组合体系桥梁的活载效应进行对比分析,来确定合理的活载计算分析方法;在活荷载作用下,通过考虑不同的主梁、桥塔及主缆刚度等结构参数,来分析研究结构主要部件的控制截面受力情况。分析结果表明:采用线性二阶和非线性理论对比分析后,主跨160 m的斜拉-自锚式悬索组合体系桥梁的活载效应计算误差在5%以内,在工程中可采用线性二阶理论进行活载作用分析;在活载作用下,副塔及主塔刚度对结构受力性能影响较小,主梁和主缆刚度对结构受力性能影响较大,在同类桥梁设计中应给予足够重视。

Based on second-order linear theory and nonlinearity theory,the live load effect of a multi-pylon cable-stayed and self-anchored suspension combination bridge is comparatively analyzed to determine the reasonable method of live load analysis. The force performance of control section of main components is analyzed under the action of live load considering different structure parameters such as rigidities of girder,pylon and cable,etc. The analysis result shows that（ 1） the calculation error about the live load effect of the160 m main span cable-stayed and self-anchored suspension combination bridge is less than 5% by using second-order linear theory and nonlinearity theory,so second-order linear theory can be used in engineering;（ 2） the changes of stiffness of main pylon and side pylon have lesser impact on the force performance of the structure,while the girder rigidity and cable rigidity have higher impact on it,which should be paid attention to in the similar bridge design.