Uplift displacement of soldier piles during stepped excavation of deep foundation pits
LOU Xiao-ming1, YANG Jing1, LI De-ning1, LIU Jian-hang12
1. Department of Geotechnical Engineering, College of Civil Engineering, Tongji University, Shanghai 200092, China; 2. Shanghai Shentong Metro Company, Shanghai 200031, China
Abstract:Based on the new understanding about rebound stress and deformation at the bottom of deep foundation pits and the generalized load transfer method considering the additional load or deformation of the soil around piles, an analytical method is proposed for the uplift of soldier piles due to excavation. It can take many factors into account, e.g., variable cross-section character of soldier piles, installation and stepped excavation of strut system and construction situation, and it can be employed to analyze the load transfer behaviors of soldier piles. Because the uplift displacement of the soldier piles is easily monitored, the calculated results are easily compared with the measured ones, which can improve the method itself and the parameters to be chosen more reasonably. Through two cases, the rationality of the proposed method to calculate the uplift displacement of soldier piles is validated. The difference between the calculated and the measured values is also discussed.
楼晓明, 杨晶, 李德宁, 刘建航. 立柱桩在深基坑分步开挖过程中的上拔位移分析[J]. 岩土工程学报, 2013, 35(1): 193-198.
LOU Xiao-ming, YANG Jing, LI De-ning, LIU Jian-hang. Uplift displacement of soldier piles during stepped excavation of deep foundation pits. Chinese J. Geot. Eng., 2013, 35(1): 193-198.
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