PBA工法地铁车站下穿桥梁影响分析

Influence analysis on subway station underpassing the bridge by PBA method

近年来,由于地铁车站的施工,出现了大量地铁车站或区间下穿城市立交桥的案例。其中,暗挖法施工导致了大量的桥梁出现纵向不均匀沉降、桥梁梁底出现裂缝等问题,因此研究地铁车站暗挖工法、优化施工工序以减少施工对邻近建筑物的影响尤为重要。本文以地铁车站常用的暗挖施工工法“洞桩法”为基础,利用有限差分计算在摩尔库伦模型基础上引入卸荷模型,对施工工序进行优化设计,得到洞桩法施工的最优工序组合,并分析不同加固措施的沉降控制效果。本文结果可为今后类似工程提供参考。

In recent years, due to the construction of subway stations, there have been a large number of cases of subway stations or sections underpassing through urban overpasses. Among them, the construction of underground excavation method has led to such problems as longitudinal uneven settlement of bridges and cracks at the bottom of bridge beams. Therefore, it is particularly important to study the underground excavation method of subway station and optimize the construction process to reduce the impact of construction on adjacent buildings. Based on the "tunnel pile method" commonly used in subway station, in this paper, the unloading model is led in based on Molar Coulomb modelby using finite different calculation, the construction process is optimized, the optimal combination of process of hole pile construction is obtained, and the settlement control effect of different reinforcement measures is analyzed.The results can provide references for similar projects in the future.