北京地铁X站暗挖段干扰降水降深预测与应用

摘要

This paper aims to research the underground water control through interfering dewatering in a Beijing subway station where the closed tubular wells can not be arranged because of the construction method (cut and cover at the both ends and underground excavation in the middle) and underground pipelines. By calculating discharge of the foundation pit and applying isogram prediction drawdown, the arrangement of dewatering wells was optimized to achieve the expected result with the consideration of the pump capacity and the environment of the construction site. With the application this method, the problem of underground water control in the region is solved. Moreover, the construction risk is decreased and the cost was saved.%以北京地铁某线X站为例，研究由于该站受施工工法（两端明挖中部暗挖）限制及交通和地下管线的影响，无场地实施封闭式管井井点降水，利用现有场地条件，在无法实施降水井封闭的区域周边布设降水井，进行干扰降水的方法对该区域地下水进行控制的问题。本文通过计算基坑涌水量，并运用等值线预测地下水降深的方法，对暗挖段地下水位降深进行计算与预测，结合预测结果并综合考虑周边环境和场地实际情况等因素，优化降水井布置，合理选择降水井泵量，通过实践检验达到了预期效果，既解决了由于无法实施封闭式管井井点区域的地下水控制问题，降低了工程风险，又节约了施工成本。