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Abstract

Based on a deep foundation pit project in Xiangyang, this paper conducted single well and group well pumping tests on site, comparing and analyzing the test data, theoretical calculations, and numerical simulation results to obtain the water charging laws of groundwater and surrounding lakes in the area. Meanwhile, the permeability coefficient of the strata was reviewed to provide necessary basis for subsequent adoption of reasonable water stopping measures. The results show that after 36 pumping wells operate at full power, they still fail to meet the requirement of lowering the groundwater level to 1 m below the basement, with high water supply degree of the aquifer. There is a significant difference in the precipitation rate between the observation wells near and far from the pumping wells, indicating poor permeability of the strata. In the early stage, the static reserves of the strata are mainly consumed. Based on on-site measured data, the average permeability coefficient calculated by the steady flow analysis method is 56.97 m/d, while that calculated by adopting the unsteady flow method is 64.5 m/d. For safety purposes, the comprehensive permeability coefficient is taken as 64.5 m/d to provide a basis for the construction of subsequent grid-connected walls. After determining the number and placement position of precipitation wells, increasing the power of the water pump appropriately can shorten the construction period. When the groundwater level drops to the design depth, precipitation can be carried out as needed, and the number of water pumps that are turned on can be appropriately reduced to decrease the total groundwater extraction amount and protect the geological environment.

Publication Date

11-8-2022

DOI

10.14048/j.issn.1671-2579.2022.05.008

First Page

44

Last Page

49

Submission Date

April 2025

Reference

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