Abstract：To calculate the pile foundation?s horizontal bearing capacity by the replacement hard shell method，a formula was established for calculating the horizontal resistance parameters according to the shear strength index of the foundation soil. The layered soft after the foundation is treated with the replacement hard shell method. The influence of the horizontal bearing capacity of the pile is revealed by the analytical calculation formula for the horizontal bearing capacity of the pile is derived. Under the conditions of embeddedness，the influence of the thickness and the shear strength index of the replacement hard shell layer on the increase of the horizontal bearing capacity of the pile was discussed and analyzed. The results revealed that the greater the internal friction angle of the hard shell soil and the thicker the thickness，and the greater the increase in the horizontal bearing capacity of the pile and the smaller the horizontal displacement of the pile top. Finally，a case of a pile foundation project in Zhejiang Province was studied，it indicated when the replacement thickness of the hard shell layer is 2–3 m(pile diameter 0.8 m)，the increase in bearing capacity basically reaches the maximum value and the horizontal bearing capacity of the pile foundation is increased by 7 to 15 times. However，the horizontal displacement of the pile top is reduced by 85% to 95%，as well as the maximum bending moment of the pile body is reduced by about half. This study could provide a reference tool for similar engineering applications.
黄朝煊，李俊杰. 置换硬壳层对成层软土中桩基水平承载特性的影响研究[J]. 岩石力学与工程学报, 2021, 40(S2): 3472-3482.
HUANG Chaoxuan，LI Junjie. Research on the influence of displacing hard shell on the horizontal bearing characteristics of pile foundation in layered soft soil. , 2021, 40(S2): 3472-3482.
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2021, Vol. 40 
