The influence of an underground shelter on the foundation pit of the pull-anchor pile row retaining structure
WAN Xiankui1, WEI Duqiang2*, JING Yongbo3, HE Xiaohui1, SHI Yufeng1,2
1. Nanchang Rail Transit Group Co., Ltd., Nanchang 330013, Jiangxi, China; 2. Key Laboratory of Geotechnical Engineering Safety and Control of Jiangxi Province, East China Jiaotong University, Nanchang 330013, Jiangxi, China; 3. Tunnel Engineering Co., Ltd., China Railway 14th Bureau Group, Jinan 250000, Shandong, China
Abstract: Based on a foundation pit project in Jingdezhen near an underground shelter, a finite element model was established using MIDAS software to simulate the excavation process of the foundation pit. The simulation results were compared with monitoring data to verify the accuracy of the finite element model. On this basis, the earth pressure, displacement and internal force of the anchoring structure of the pull-anchor foundation pit were studied, and the influence range of the underground shelter was obtained by comparing the influence of different horizontal distance underground shelters on the deformation of the supporting structure. The results of the study indicated that the earth pressure behind the pile would decrease and then increase when there was an air-raid shelter. The earth pressure at the top of the air-raid shelter began to decrease and the bottom began to increase 55 kPa; when the foundation pit was excavated to the depth of the air-raid shelter, the maximum horizontal displacement value of the enclosing pile was reduced by 15% compared with that without the air-raid shelter, the influence range of underground shelter on the foundation pit was about 2.5D(D is the diameter of the underground shelter). Both the maximum bending moment point and the reverse bending point would show a downward trend, and the maximum bending moment value would increase with the increase of the excavation depth. The maximum bending moment was increased by 20%.
万先逵,魏度强,荆永波,何小辉,石钰锋. 某地下防空洞对拉锚式排桩围护结构基坑的影响[J]. 隧道与地下工程灾害防治, 2020, 2(1): 97-104.
WAN Xiankui, WEI Duqiang, JING Yongbo, HE Xiaohui, SHI Yufeng. The influence of an underground shelter on the foundation pit of the pull-anchor pile row retaining structure. Hazard Control in Tunnelling and Underground Engineering, 2020, 2(1): 97-104.
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