Technology of Lowering Confined Water for Irregular Foundation Pit with Metro Foundation "Pit-in-pit"

Abstract:

In the construction of deep, large, and irregular foundation pit, Shanghai Museum of Natural History, with another foundation pit of Metro Line 13 in it, lowering confined water has an large effect on the safety of the foundation pit construction and the protection of the surrounding environment. Many confined water pumping tests were carried out in this construction, and with the help of numerical simulation, the results indicate that the dewatering effect of pumping wells with filter tube of 8 m is better, although two different pumping wells with filter tube of 4 m and 8 m have the same flow rate and influential radius; the barrier effect is not obvious if the depth of underground continuous wall inserted into confined water layer is less than one third of the thickness of confined water layer; it takes less than 360 minutes to reach 80% of the total drawdown, the drawdown decreases to 90% of the total drawdown 10 minutes after the wells are stopped. Then the schemes of dewatering and pumping wells cooperated with the excavation are developed based on the seepage laws.

• Periodical: Applied Mechanics and Materials (Volumes 193-194)
• Pages: 1183-1191
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.193-194.1183
• Online since: August 2012
• Authors: Ji Cong Zou, Shun Hua Zhou, Quan Mei Gong
• Keywords: Confined Water, Irregular Pit-in-Pit Excavation, Numerical Simulation, Pumping Tests, Well Plugging

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