波形钢腹板组合箱梁矮塔斜拉桥塔墩梁固结段受力分析

Analysis of Mechanical Behavior of Pier-Girder Anchorage Section of Extradosed Cable-Stayed Bridge with Corrugated Steel Web Composite Box Girders

为研究波形钢腹板矮塔斜拉桥塔墩梁固结区域的复杂受力情况,采用有限元法对该处进行精细化数值模拟,分析单箱三室波形钢腹板截面总剪力中腹板承担剪力的比例,直、斜腹板承担的剪力及剪应力比较,内衬混凝土对腹板剪应力分布的影响,以及顶、底板端部正应力的整体计算与局部计算比较分析。结果表明:塔墩梁固结段波形钢腹板承担的剪力远小于常规梁段;直、斜腹板剪应力分布规律一致,但由于单箱三室截面中各室宽度不同,各腹板承担的剪力也不同,设计中应考虑此影响;矮塔斜拉桥主梁承担剪力较小,设计中可省略内衬混凝土设置;整体模型计算中得到的顶、底板正应力基本偏大于局部模型计算结果。

In order to study the complicated mechanical behavior of the pylon-pier-girder fixed region, the finite element method was adopted to conduct the elaborate numerical simulation of the region to analyze the proportion of the overall shear force bored by webs in the cross sections of the three-cell single box corrugated steel webs, the comparison of the shear force and shear stress bored respectively by the straight and oblique webs, the impact of lining concrete on the distribution of the web shear stress and the analysis and comparison of the general calculation and local calculation of the normal stress at the ends of the top and bottom plates. The results of the analysis indicate that the shear force bored by the corrugated webs in the pylon-pier-girder fixed region is less than that bored by the conventional girder; the distribution pattern of the shear force in the straight and the oblique webs are the same, but due to the different width of the cells of the three-cell single box cross section, the shear force bored by the webs are different, which should be taken into consideration in the design; the shear force bored by the main girder of the extradosed cable-stayed bridge is relatively less, the installation of the lining concrete can be ignored in the design; the normal stress in the top and bottom plates got in the general model calculation is basically greater than the values got in the local model calculation.