Waterproof casing in the construction of the problem should be how to deal with?

Waterproof casing trench excavation process often appears side slope collapse, bottom of the tank soak, bottom of the tank overdigging, trench section does not meet the requirements of some quality problems, prevention methods.
 
1. prevent side slope collapse: according to the soil category, the mechanical properties of the soil to determine the appropriate slope of the slot gang. The slope of straight trench is generally 1:0.05. For deeper trench, it is appropriate to excavate in layers. The excavated soil should be properly arranged and stacked, generally on both sides of the trench. The distance between the foot of the slope under the pile and the edge of the trench is determined according to the depth of the trench, soil quality and the slope of the trench edge, and the smaller distance should be 1.0m.
 
2. Control of trench section: determine the reasonable trench section and width of the bottom of the trench. Grooving section is determined by the width of groove bottom, excavation depth, groove bottom, slope of each layer and the width of inter-layer stay. The width of the bottom of the slot should be the width of the pipe structure plus the working width on both sides. Therefore, when determining the excavation section, we should consider the production hidden danger and engineering quality, so that the groove section is reasonable.
 
3. prevent the bottom of the tank soaking: the rainy season construction and installation of flexible waterproof casing, should be stacked around the trench closed earth ridge, if necessary, to dig a drainage ditch outside the ridge to prevent rainwater flow into the tank. Below the water table or shallow stagnant water lots digging trench, construction units should be required to set up drainage ditches, water collection wells, pumping water. The next process should be carried out immediately after the bottom of the trench, otherwise, the bottom of the trench should be left 20cm soil layer is not dug as a protective layer.
 
4. Prevent over-excavation at the bottom of the trench: Measure and check the elevation of the bottom of the trench when digging the trench. When using machinery to dig the slot, leave 20cm soil layer above the designed slot bottom elevation to be dug manually. In case of over-excavation, the following measures should be taken: fill with gravel to the design elevation, or fill the soil ramming, its compactness is not less than the original foundation compactness.
 
The above is the waterproof casing in the construction of the problem of handling, I hope that when you encounter problems can help you.