|Table of Contents|

Research on Sliding Radius of Basal Heave Failure of Excavation in Soft Soil Area(PDF)

《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]

Issue:
2021年06期
Page:
90-97
Research Field:
软土基坑设计与变形控制
Publishing date:

Info

Title:
Research on Sliding Radius of Basal Heave Failure of Excavation in Soft Soil Area
Author(s):
CHENG Xue-song1; 2;  ZHEN Jie2;  ZHENG Gang1; 2;  WANG Zhi-yong3;  WANG Zhe3;  SONG Xu-Gen3
(1. Key Laboratory of Coast Civil Structure Safety of Ministry of Education, Tianjin University, Tianjin 300072, China; 2. School of Civil Engineering, Tianjin University, Tianjin 300072, China; 3. Road Traffic Design and Research Institute, China Railway Siyuan Survey and Design Group Co., Ltd., Wuhan 430063, Hubei, China)
Keywords:
basal heave;  soft soil;  discontinuous layout optimization method;  insertion ratio;  sliding radius
PACS:
TU433
DOI:
10.19815/j.jace.2021.08051
Abstract:
In order to study the failure mode of excavation basal heave in soft soil area and determine the reasonable basal heave sliding surface, the discontinuous layout optimization method was adopted to analyze the sliding surface of the excavation basal heave with different insertion ratios of the retaining structure. The power function expressions of the soil strength and the critical insertion ratio of the retaining structure at different excavation depths were obtained through a lot of calculations, which can judge whether the sliding surfaces pass through the end of the retaining structure. By analyzing the relationship between the normalized basal heave sliding radius of excavations and the insertion ratio of the retaining structure when the envelope was relatively small, the logarithmic expression and its coefficient table were obtained, which can modify the sliding radius of the traditional slip circle method. Finally, the safety factor calculated by modifying the sliding radius was compared with the numerical simulation results, which verified the reliability of the sliding radius formula. The results show that the sliding surface passes through the end of the retaining structure when the insertion ratio is larger(the insertion ratio of the retaining structure is larger than the critical insertion ratio). The sliding surface does not pass through the end of the retaining structure when the insertion ratio is relatively small, which needs to be improved. The proposed correction method can provide a reference for the selection of the sliding radius when analyzing the basal heave stability of excavations with thick soft clay. At the same time, it also solves the problem of changes irrationally in the safety factor of traditional slip circle method when the insertion ratio is small.

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Last Update: 2021-11-01