地铁隧道下穿施工对桥梁地上结构的影响研究

Study on the influence of underground tunnel construction by mining method on bridge structure on the ground

为了对隧道施工对既有桥梁地上结构影响进行分析,建立ABAQUS数值计算模型,对桥梁上部结构的位移变形及内力响应规律进行了研究。研究表明:上部结构沉降变形可分为两阶段:均匀沉降阶段和局部加速沉降阶段;地梁与盖梁沉降变形规律相同,可用地梁沉降近似代替盖梁沉降,盖梁与地梁弯矩变化规律相似,一般情况下,地梁弯矩值大于盖梁弯矩值,研究结果对今后类似下穿施工具有一定参考意义。

In order to analyze the influence of tunnel construction on the ground structure of existing bridge,this paper establishes ABAQUS numerical calculation model to simulate the whole process of tunnel underpass construction by mining method. Through the model verification,the displacement deformation and internal force response of the bridge superstructure are studied. The results show that the settlement and deformation of superstructure can be divided into two stages,uniform settlement stage and local acceleration settlement stage,the settlement and deformation rules of ground beam and cap beam are the same,and the numerical difference is not significant,so the settlement of ground beam can be used to replace the settlement of cap beam approximately,the bending moment change rules of cap beam and ground beam are similar,in general,the bending moment value of ground beam is greater than that of cap beam. The research results obtained in this paper have certain guiding significance for similar underpass construction in the future.