半漂浮宽箱混凝土斜拉桥剪力滞效应研究

Study on shear lag effect of semi-floating cable-stayed bridge with wide concrete box girder

以某半漂浮宽箱混凝土斜拉桥为例,采用MIDAS/Civil软件建立有限元模型,分析了施工阶段和成桥移动荷载作用下箱梁的剪力滞效应,并进行了纵桥向和横桥向的对比分析。结果表明:半漂浮体系斜拉桥混凝土箱梁剪力滞效应沿纵桥向有明显的分区效应;施工阶段和移动荷载作用下箱梁的剪力滞效应沿纵桥向和横桥向均呈现较大的规律性,即纵桥向在支点和桥塔附近箱梁剪力滞明显,横桥向剪力滞系数曲线在不同截面处呈现出不同的曲线形状。

With a semi-floating wide box concrete cable-stayed bridge as an example,using Midas / Civil software to establish the finite element model to analyze the shear lag effect of box girder under the construction stage and completed bridge stag moving load,and comparative analyze the longitudinal and transverse direction of the bridge. Calculation results show that the shear lag effect of the concrete box girder of cable stayed-bridge with semi-floating system has obvious effect on the longitudinal direction; the shear lag effect of box girder under construction stage and moving load shows great regularity along longitudinal direction and transverse direction,which means that the box girder shear lag is obviously in the longitudinal direction near the support point and bridge tower,the curve of the transverse direction shear lag is different in different sections.