Skewness distribution patterns of surface settlement considering overload effect
LI Yuan-xun1, ZHU Yan-peng2, YE Shuai-hua2, MA Xiao-rui2
1. School of Civil Engineering, Qinghai University, Xining 810016, China; 2. Western Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, China
Abstract：How to consider the influences of surrounding environment and determine the patterns of surface settlement curve is the primary problem in the calculation of surface settlement. The existing formulas are mostly obtained under the assumption that the pit is under the premise of no overload or single overload, and their application is limited. Therefore, different effects of the equivalent overloads are derived, and then the prediction model for skewness distribution curve of surface settlement is established considering the surface settlement under different overloading types based on the principles of formation damage method. The relevant formula is derived in order to get reasonable, reliable and satisfactory forecast results of surface settlement. For a practical project, a comparison is made among results by the proposed method, the simulated results of numerical analysis software Plaxis-2D and the measured settlement values. The results show that the effect of overloading is necessary to be considered for the reason that it has induced a greater increase in the surface settlement and also made the maximum settlement point moves significantly toward the foundation pit. In addition, the obtained results are in good agreement with the measured settlement values, and the computational accuracy is higher. The proposed method for surface settlement of deep foundation pits is improved, and it can be helpful for other similar projects.
李元勋, 朱彦鹏, 叶帅华, 马孝瑞. 超载作用下地表沉降偏态分布模式研究[J]. 岩土工程学报, 2018, 40(S1): 171-176.
LI Yuan-xun, ZHU Yan-peng, YE Shuai-hua, MA Xiao-rui. Skewness distribution patterns of surface settlement considering overload effect. Chinese J. Geot. Eng., 2018, 40(S1): 171-176.
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