In order to prevent the inrushing caused by deep excavations, dewatering measure has to be adopted to
decrease the confined water level. In this study, the responses of the strata and supporting system to dewatering
in deep excavations are investigated through numerical simulations and case studies. Coupled fluid-mechanical
analyses are performed by the use of the numerical software, FLAC3D. The responses of the ground settlement,
base heave and interior columns to the excavation and dewatering are analyzed. Numerical results indicate that
the dewatering measure can effectively reduce the uplift of the subsurface soil in the excavation, and decrease
the vertical displacement of the supporting system. In addition, field data of two case histories show the similar
responses and confirm the validation of the numerical results. Based on the analyses, dewatering in the confined
aquifer is recommended as a construction method for controlling the vertical displacement of the strata and
supporting system in deep excavations.
XIAO Xiao (肖潇), ZHANG Yangqing (张扬清), LI Mingguang* (李明广), WANG Jianhua (王建华)
. Responses of the Strata and Supporting System to Dewatering in Deep Excavations[J]. Journal of Shanghai Jiaotong University(Science), 2017
, 22(6)
: 705
-711
.
DOI: 10.1007/s12204-017-1884-7
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