Monitoring and analysis of stress and deformation of shield working well excavation in upper soft and lower hard soil layer
WEI Gang1, HUANG Shiyu2, JIANG Chengwu1, YU Xingfu3, WANG Xinquan1
1. Department of Civil Engineering, Zhejiang University City College, Hangzhou 310015, Zhejiang, China; 2. College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, Zhejiang, China; 3. Ningbo Metallurgical Investigation & Design Research Co., Ltd., Ningbo 315041, Zhejiang, China
Abstract: Based on one typical excavation project of shield working well in Hangzhou where the soft soil was over the hard soil, this paper monitored and analyzed the horizontal displacement of the wall, ground settlement, surrounding building settlement, and strut force during its excavation. The results showed that: with the excavation of the foundation pit in upper soft and lower hard soil layer, the distribution of the horizontal displacement of the wall along the depth of the foundation pit had two forms: single peak and double peak, the maximum horizontal displacement of the wall was between 0.56‰-0.59‰ H(H is the excavation depth of the working well); The maximum horizontal displacement of the wall was about 5 m above the soil-rock interface. The ground settlement curves were mainly in the form of “inverted triangle-shaped” and “spoon-shaped”, the sensitive area of the settlement was mainly distributed in the range of about 0.36-0.73 H from the edge of the foundation pit and the maximum settlement was about 1.36‰-2.61‰ H; The excavation phase of the soil below each support was the main growth period of the corresponding strut force. Thereinto, the strut force value of the concrete support was affected by the curing time, and it must be guaranteed to reach 28-day strength before excavation.
魏纲,黄时雨,蒋丞武,虞兴福,王新泉. 上软下硬地层盾构工作井开挖受力与变形监测分析[J]. 隧道与地下工程灾害防治, 2020, 2(4): 29-36.
WEI Gang, HUANG Shiyu, JIANG Chengwu, YU Xingfu, WANG Xinquan. Monitoring and analysis of stress and deformation of shield working well excavation in upper soft and lower hard soil layer. Hazard Control in Tunnelling and Underground Engineering, 2020, 2(4): 29-36.
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2020, Vol. 2 
