西北及沿海一带,有很多城市和工矿企业往往要在潮相沉积或海相沉积的地层中以管井取用深层地下水。这些地层的含水层多系细砂或粉砂所组成。在细、粉砂地层中所建的管井,往往由于设计和安装不当,致使含水层中的细、粉砂不断涌入井内,有的管井投产时间不长,就因砂粒堵塞过滤器,而无法继续取水,有的管井则由于涌砂过多而造成井管歪斜,泵轴磨损,基础沉陷,房屋坍塌而报废。据初步调查,××线六个铁路给水站,在 In the northwest and coastal areas, many cities and industrial and mining enterprises often use deep wells to access deep-seated groundwater in tidal deposits or marine deposits. The aquifers of these formations are mostly composed of fine sand or silt. The wells built in fine and silty sand formations are often due to improper design and installation, resulting in fine and silty sand in the aquifers continuously flooding into the wells. Some of the wells are not put into operation for a long time, and they cannot be blocked because of sand particles. Continuing to take water, some pipe wells are caused by too many gushing well pipes skew, pump shaft wear, foundation sinking, housing collapsed and scrapped. According to preliminary investigations, the X× line of six railway water supply stations was