04无砂大孔混凝土管井降水工程.doc

一、 工艺特点
沿高层建筑基础或在地下水位以下的建筑物基坑的四周采用泥浆护壁循环钻机成孔，然后每隔一定距离埋设一个无砂大孔混凝土管井，形成环状布置，从单孔管井用潜水泵抽水至连续总管内，然后排至沉淀池内，再排送至污水管井。
二、 材料、机械准备
滤水井管、循环成孔钻机、潜水泵、吸水管、空压机、排水管、水泵控制自动系统、3～5mm豆石、木底座或混凝土底座、沥青、麻布等。
三、 施工准备
1、 首先要了解地质勘探资料、掌握地下土质和水位变化情况，特别是地下流砂层情况，以便确定钻孔工艺和准备必要材料。
2、 根据总的平面布置和所开挖地下工程的面积，确定正式管井和观测管井的数量、位置，排水管位置流向，沉淀池位置以及与污水管道连按地点。
3、 对设置井点位置进行平整、放线，用白次标明其位置。
四、 管井构造
管井的滤管为无砂大孔混凝土管，采用粒径为3～5mm的豆石加水泥按6:1左右比例预制而成，

First, technological features
High-rise buildings along the base or foundation in the ground water level around the building below the Wall by mud circulation drill hole, and then at regular intervals from the laying of a concrete tube wells without sand big hole to form a circular arrangement, from the single-hole tube well with submersible pump to continuous pumping mains, the then exclusive to the sedimentation tanks, and then sent to waste water tube wells row.
Second, materials, mechanical preparation
Treatment well pipe, circular hole drilling, submersible pumps, suction, air compressors, pipes, pumps automatic control systems, 3 ~ 5mm bean stone, wood base or concrete base, asphalt, linen, etc..
Third, construction preparation
1, we must first understand the geological exploration data, soil and underground water level control, especially in dirty sand in order to determine drilling process and prepare the necessary materials.
2, according to the general layout of underground excavation works and the area to determine the official number of tube wells tube wells and observation, location, location of drainage flow, sedimentation tanks and sewer locations, and even by location.
3, set well point position on the formation, laying and marked its position with a white sub.
4, tube well construction
Tube wells without sand filter tube macroporous concrete pipe, with diameter of 3 ~ 5mm of beans stone with precast concrete made according to the proportion of about 6:1,