高铁32 m简支箱梁梁端局部应力研究

Study on Local Stress at End of 32-m Simple-supported Box Girder of High-speed Railway

基于某高速铁路32 m简支箱梁设计方案,通过建立有限元模型,研究了梁端局部应力的影响因素,并确定了调整方案。研究表明,梁端局部应力受钢束影响较大,而对支座横向间距、竖向荷载、结构尺寸等因素不敏感。通过减小钢束规格、竖弯角等均可减小主拉应力。钢束布置同样对梁端局部应力有影响,通过增加或减少相应位置的钢束规格可以有效降低主拉应力。最后对推荐方案梁端进行了配筋检算,钢筋应力及裂缝宽度均满足规范要求。

Based on a design scheme of 32-m simple-supported box girder of high-speed railway, the article studies the influence factor of local stress at the girder end through the establishment of the finite element model, and determines the adjustment scheme. The study result shows that the local stress at the girder end is greatly influenced by the steel cable, but is not sensitive to the transverse spacing, vertical load and structural sizes of the support. The decrement of steel cable sizes and vertical bends can all decrease the principal tensile stress. The layout of steel cable also has the influence on the local stress at the girder end.The increment and decrement of the steel cable sizes at the relative positions can effectively reduce the principal tensile stress. The article checks and calculates the reinforcing bars at the girder end of the recommended scheme. The steel bar stress and crack width all satisfy the standards and requirements.