基坑施工中的地下水处理及工程实例.rar

前言
当基础深度在天然地下水位以下时，在基础施工中常常会遇到地下水的处理问题。一般认为，基坑开挖要具备以下的必要条件：首先保持基坑干燥状态，创造有利于施工的环境；其次是确保边坡稳定，做到安全施工，如果忽视这些必要条件，其后果是严重的。有的基坑积水或土质稀软，工人难以立足，无法施工；有的出现“流砂现象”导致边坡塌方，地质破坏；有的内部基坑土体发生较大的位移，影响邻近建筑物的安全。之所以会出现这些异常情况，都是由地下水引起的。所以，在基坑施工中应对地下水的处理给予应有的重视。

一、 地下水的人工处理
地下水的处理有多种可行的方法，从降水方式来说可总分为止水法和排水法两大类。止水法，即通过有效手段，在基坑周围形成止水帷幕，将地下水止于基坑之外，如沉井法、灌浆法、地下连续墙等；排水法是将基坑范围内地表水与地下水排除，如明沟排水、井点降水等。
止水法相对来说成本较高，施工难度较大；井点降水施工简便、操作技术易于掌握，是—种行之有效的现代化施工方法，已广泛应用。本文结合工程实例对井点降水法作一简要介绍。
井点降水法，它是在拟建工程的基坑周围设能渗水的井点管，配置一定的抽水设备，不间断地将地下水抽走
Preface
When the foundation depth below the natural water table, often in basic construction problems encountered in the treatment of groundwater. Is generally believed that excavation should have the following necessary conditions: first, to maintain foundation dry state, to create an environment conducive to construction; followed to ensure stability, to achieve security, construction, ignore these necessary conditions, the consequences are serious of. Some pit water or soil softer and workers to gain a foothold, not construction; some a "quicksand phenomenon" lead to slope landslides, geological damage; some of the soil within the pit, large-displacement, affecting adjacent buildings safety. The reason why these anomalies occur are caused by groundwater. Therefore, groundwater in the foundation excavation should pay due attention to the treatment.

I. Artificial groundwater treatment
There are several possible water treatment methods can score from the precipitation method for water law and water law up to two categories. Sealing method, that is through effective means, waterproof curtain formed around the pit, the pit stop outside the ground, such as the open caisson method, grouting, diaphragm walls, etc.; drainage method is to pit the surface water area in the Mainland and water exclusion, such as the open ditch drainage, dewatering, etc..
Sealing method is relatively costly, difficult construction; Dewatering simple operation technology easy to master, is - kind of effective modern construction methods, has been widely applied. With practical examples of the wells to make a brief introduction.
Wells, which is located around the proposed excavation works well point to water seepage, configure some pumping equipment, uninterrupted take away the groundwater