Transformation of load-settlement curve based on load transfer at pile-soil interface
MA Wen-jie1,2, WANG Xu3, WANG Bing-long1,2, WANG Bo-lin3
1. Key Laboratory of Road and Traffic Engineering of the Ministry of Education,Tongji University,Shanghai 201804,China; 2. Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety,Shanghai 201804,China; 3. School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China
Abstract：The self-anchoring test is a new method to detect the bearing capacity of pile foundation. The indoor model tests and the numerical simulation are used to explore the difference of the Q-s curves between the static load tests and the self-anchoring tests, and to realize the transformation of the results from the self-anchoring to static load tests. The results show that the settlement of foundation piles in the static load tests is larger than that of the self-anchoring tests, the resistance is developed in advance and its ultimate bearing capacity is smaller. Both the ratios of the ultimate bearing capacity and the elastic slopes of Q-s curve of the self-anchoring tests and static load tests are exponential with the anchoring depth of the foundation piles. Based on the parameter analysis of foundation soil of the measured data, the logarithmic load transfer model is proposed, the bearing behavior of the foundation piles can be solved by the iterative algorithm, and the load transfer at pile-soil interface can achieve the transformation of the Q-s curve of the foundation piles from the self-anchoring tests to the static load tests, which is verified by the indoor model tests. The research results may provide a useful reference for testing the bearing capacity of the self-anchoring tests in pile foundation engineering.
马文杰, 王旭, 王炳龙, 王博林. 基于桩土界面荷载传递的荷载-沉降曲线转化研究[J]. 岩土工程学报, 2021, 43(S1): 41-46.
MA Wen-jie, WANG Xu, WANG Bing-long, WANG Bo-lin. Transformation of load-settlement curve based on load transfer at pile-soil interface. Chinese J. Geot. Eng., 2021, 43(S1): 41-46.
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