Responses of the Strata and Supporting System to Dewatering in Deep Excavations

doi:10.1007/s12204-017-1884-7

摘要/Abstract

摘要： 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.

关键词: deep excavations, column, confined water, numerical simulation, dewatering measure

Abstract: 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.

Key words: deep excavations, column, confined water, numerical simulation, dewatering measure

中图分类号:

TU 473.3

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]. 上海交通大学学报（英文版）, 2017, 22(6): 705-711.

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 Jiao Tong University (Science), 2017, 22(6): 705-711.

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