Analysis on Dewatering Test of Foundation Pit in Stratum with Small Permeability
(1 Bridge & Tunnel Engineering Company of the Third Engineering Group Co., Ltd. of China Railway, Handan 056036；2 Zhongkan Metallurgical Geotechnical Investigation Design and Research Institute Co., Ltd, Baoding 071000；3 Urban Rail Transit Engineering Co. of China Railway First Group Co., Ltd., Xi′an 710000)
Abstract：
It is often to encounter silt clay with small permeability during excavation of metro foundation pit, and difficult to dewater effectively with tube well method, the residual water could significantly affect the safety of foundation pit. Dewatering test and numerical simulation were conducted to study the dewatering techniques by tube well and vacuum tube well. The results show that the volume of water inflow in condition of vacuum tube dewatering is 1.1-1.4 times larger than that of tube well method, with obvious time effect and shorter construction period; the drawdown in condition of vacuum tube well is 1.2-1.6 times larger than that of tube well method; the phreatic line of dewatering is more flat and the affected radius of dewatering increases significantly, which is favorable to increase interval of dewatering wells and obtain good economic benefit.
REN Wei1 WANG Song2 WANG Long3
.Analysis on Dewatering Test of Foundation Pit in Stratum with Small Permeability[J] MODERN TUNNELLING TECHNOLOGY, 2019,V56(4): 188-193
2019, Vol. 56 