大翼缘宽箱梁矮塔斜拉桥施工阶段剪力滞效应分析
Analysis of shear lag effect in construction stage of wide box girder extradosed cable-stayed bridge with large flanges

以某大翼缘宽箱梁矮塔斜拉桥为工程背景，建立ANSYS实体有限元模型对悬臂施工过程进行精确模拟，分析最大悬臂阶段所有截面剪力滞效应的分布规律；研究主梁典型截面在施工过程中的剪力滞效应变化，并与实测结果进行对比。研究结果表明：最大悬臂阶段的顶板剪力滞效应沿悬臂方向由正剪力滞效应过渡为负剪力滞效应；随悬臂施工过程的推进，典型截面内箱室顶板剪力滞系数逐渐减小，翼缘板剪力滞系数逐渐增大，剪力滞系数趋于稳定；实测数据与理论计算结果随施工进程的变化趋势基本一致，验证了理论分析的正确性。
Taking the extradosed cable-stayed bridge with a wide flange and wide box girder as the engineering background, the ANSYS solid finite element model is established to simulate the cantilever construction process accurately. The distribution law of shear lag effect of all sections in the maximum cantilever stage is analyzed. The shear lag effect of the typical section of the main girder during construction is studied and compared with the measured results. The results show that the shear lag effect of the roof in the maximum cantilever stage changes from the positive shear lag effect to the negative shear lag effect in the cantilever direction. With the advance of the process of cantilever construction, the inner chamber roof shear lag coefficient in typical section decreases, the shear lag coefficient of flange increases, and the shear lag coefficient tends to be stable. The measured data are basically consistent with the theoretical calculation during the construction stage, and the correctness of the theoretical analysis is verified