Layered water stop device and method for preventing and treating gushing of side wall of confined water of foundation pit depressurization well

Abstract

The invention relates to a layered water stop device and method for preventing and treating gushing of the side wall of confined water of a foundation pit depressurization well. The device comprises clay balls and water-swelling rings, the clay balls and the water-swelling rings are filled into the position between a well casing and a drill hole of the depressurization well and are arranged at intervals one by one in the height direction, and the water-swelling rings are arranged outside the well casing in a sleeving manner; the water-swelling rings are provided with water-swelling materials and waterproof films wrapping the water-swelling materials, and the waterproof films are broken after the water-swelling rings are placed in place, so that the water-swelling materials are exposed; andwhen the confined water leaks, the water-swelling materials in the water-swelling rings swell in water to form a vertical waterproof body. Compared with the prior art, the device has the advantages that the anti-seepage performance of the depressurization well can be further improved under the condition that the hole sealing quality of the clay balls is unknown, and especially under the conditions that the sealing quality of the clay balls is poor, consequently the sealing effect is poor, and the confined water leaks upwards along the bottom of the well, a seepage path of the confined water can be directly blocked; and potential safety hazards caused by leakage of the depressurization well are eliminated.

Description

technical field [0001] The invention belongs to the technical fields of geological engineering, geotechnical engineering, and foundation pit engineering, and in particular relates to a layered water stop device and method for preventing and controlling surges of pressurized water side walls of foundation pit depressurization wells. Background technique [0002] The foundation pit dewatering is when the foundation pit is excavated, the groundwater level is higher than the excavation bottom surface, and the groundwater will continue to seep into the pit. Precipitation work due to the bottom piping and the decline of the bearing capacity of the foundation. In modern geotechnical engineering and foundation pit engineering dewatering construction operations, well point dewatering is a common and important treatment method. Well point dewatering is to arrange a certain number of depressurization wells around the foundation pit before excavation of the foundation pit. During the e...

AI Technical Summary

Problems solved by technology

Clay balls are commonly used for sealing holes and preventing seepage in depressurization wells. However, since clay balls are located at the bottom of the well, between the well pipe and the well wall, its sealing quality is often difficult to control to achieve a complete plugging effect. Sometimes it will cause the pressurized water to seep upwards along the side wall, which will seriously cause sudden surge, so that the depressurization well cannot play the role of depressurization

The applicant of the present invention found that the treatment measures for the side wall leakage problem have not been taken into account in the construction process of the decompression well at present, and it is urgent to conduct research on how to overcome the poor quality of clay balls and the side wall leakage of the decompression well

Images