1、 When the underground water level needs to be lowered during the construction of the steel mesh skeleton polyethylene composite pipe, the following requirements shall be met:
1. Where the drainage pipe is close to the building, when lowering the groundwater level, preventive measures shall be taken to prevent the drainage from affecting the adjacent building.
2. The method of lowering the groundwater level shall be selected according to the permeability of soil layer, precipitation depth, equipment conditions, etc.
2、 The construction dewatering quality shall meet the following requirements:
1. There shall be no ponding in the groove of the polyethylene composite pipe with steel mesh framework, and construction with water shall be strictly prohibited. The groundwater level should be lowered to 0.5m below the bottom of the tank.
2. In the area where the groundwater level is higher than the bottom elevation of the excavated trench, the groundwater level shall be reduced to 0.5m below the low point of the trench bottom; After the pipeline is laid, it is not allowed to stop lowering the groundwater during backfilling. After the pipeline is stable, the groundwater can be stopped.