摘 要 基坑降水是基坑开挖工程的重要条件，它不但为地下工程提供安全和干燥的施工环境，而且增加了土层的稳定性，防止边坡开裂和崩塌，防止挖方底部的土层隆起或翻浆，保证工程顺利进行。本文结合北京蓝色港湾基坑工程的工程地质和水文地质条件进行了该项目的基坑降水设计，降水目的在于完成工程前期的降水工作，保证工程的顺利开展。首先根据基坑具体条件及工期等各方面的要求选择了管井降水方法，又根据地下水情况和土层情况结合周边环境选取潜水完整井的计算模式。按照《建筑基坑支护技术规程》（JGJ120—99）进行降水的设计计算和降水系统的设计，完成了基坑涌水量、井数、井间距、井深及布置形式、降水沉降计算等各方面的设计内容，并结合场地周边环境对特殊地段进行了相应的处理，以便达到更好的降水效果。 关键词：基坑降水; 管井; 潜水完整井 Abstract According to the engineering geology and hydrology geology conditions of Beijing Blue Bay Building, the design of foundation pit dewatering of the building is introduced in this thesis. The purpose of the design is to complete the dewatering work at the first term of the construction, which can insure the building go on successfully. First, based on the requests of construction period etc. the method for dewatering is chosen. Then, according to the conditions of underground water and horizon of soil, the calculation pattern is chosen. Based on the related dewatering standard, the calculation and the design of dewatering system are completed, including the number of wells, the spacing of the wells, and the depth of the wells etc. Finally, according to the perimeter environment, some special districts for dewatering are treated, which can get a good dewatering effect. Keywords: the Foundation Pit of Dewatering; Tubular Well; Groundwater Well 目 录 第一章 绪 论 第一节 选题意义 第二节 主要内容 第二章 工程概况 第一节 工程简介 一、项目概况 二、工程周边情况 第二节 工程地质和水文地质条件