Spatial effects of deformation due to excavation in soft clay
LOU Chun-hui1, XIA Tang-dai1, LIU Nian-wu2
1. Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China; 2. School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou 310018, China
Abstract：The deformation due to excavation in soft clay areas has considerable spatial effects. To investigate the deformation characteristics, a large-scale deep excavation project in Wenzhou is monitored, the settlements and cracks of the ground and adjacent buildings are observed and analyzed through two directions: perpendicular to the retaining wall and paralleled to the wall, and the distribution characteristics of the ground settlement are summarized. The field measurements show that the corner has inhibition effect on the wall deflections and ground settlements. In the vertical direction, the buildings in the range of 2 He outside the excavation have large differential settlement, and the maximum angular variable reaches 1/1300. The longitudinal cracks are observed from 0.4 He to 1.2 He (the maximum excavation depth) on the parallel direction, the large rate of settlement change may damage the road or the structures. In addition, the total and differential settlements of the buildings on pile foundation are significantly smaller than those on strip foundation.
楼春晖, 夏唐代, 刘念武. 软土地区基坑对周边环境影响空间效应分析[J]. 岩土工程学报, 2019, 41(S1): 249-252.
LOU Chun-hui, XIA Tang-dai, LIU Nian-wu. Spatial effects of deformation due to excavation in soft clay. Chinese J. Geot. Eng., 2019, 41(S1): 249-252.
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