A well pipe for a dewatering well and a method for plugging a reserved hole in a foundation pit

Abstract

The invention discloses a method for blocking a reserved hole of a foundation pit. The method comprises the following steps that (1) the reserved hole of the foundation pit is blocked; and (2) a precipitation well is blocked, i.e., a water pump is taken out after concrete for blocking the reserved hole reaches a certain strength, a well casing body is quickly filled with materials which slowly expand when encountering water, meanwhile, a drain valve of the well casing body is opened, and the water pump is used for continuously drawing water for a drainage port in the side face of the drain valve; it is ensured that the water level in the well casing body is lower than the height of a first blocking plate which is prearranged on the upper portion of the drain valve, and the first blocking plate is welded; and micro-expansion concrete is poured on the first blocking plate until reaching the position of a prearranged second blocking plate, and the second blocking plate is welded. According to the method for blocking the reserved hole of the foundation pit and the precipitation well for the reserved hole of the foundation pit, the reserved hole and the precipitation well can be blocked successfully when ground water pressure is large or water inflow is large, the blocking quality is good, blocking is easy and convenient, the construction cost is low, and the method has popularization value.

Description

technical field [0001] The invention relates to a method for sealing a reserved hole in a foundation pit, and belongs to the technical field of geotechnical engineering construction. Background technique [0002] With the unprecedented development of geotechnical engineering in my country, the number of foundation pit projects in my country is increasing, and the scale is also increasing. The depth of foundation pits is also deepening, and the complex underground geological conditions make the foundation pit precipitation scientific and rapid. Rise. At present, there are many large-scale and deep foundation pits in our country. It is inevitable that there will sometimes be some post-construction sites such as reserved openings and post-pouring belts in the foundation part. These parts are often blocked when there is underground pressurized water. It is more difficult, especially when the precipitation wells are basically not used in the later period. In this way, the precipi...

AI Technical Summary

Problems solved by technology

At present, there are many large-scale and deep foundation pits in our country. It is inevitable that there will sometimes be some post-construction sites such as reserved openings and post-pouring belts in the foundation part. These parts are often blocked when there is underground pressurized water. It is more difficult, especially when the precipitation wells are basically not used in the later period. In this way, the precipitation wells can only be added in the reserved holes so that the concrete will not seep upward during the pouring process. This method can ensure the concrete pouring If such measures are not taken, more upward water channels will be formed inside the concrete under water pressure, which cannot guarantee the quality of concrete construction density. The use of dewatering wells in the pit to pump water is to ensure the stability of the bottom plate of the foundation pit against inrush. Useful ways

However, at this time, most of the underground confined water has gathered in the dewatering wells of such foundation pits and the decompression wells left on the original foundation floor. Such foundation pits have high water pressure and large water volume. rise, making the plugging of such wells even more difficult, how to plug such wells is one of the problems to be solved in the present invention

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