Improved solution for predicting settlement of tubular-pile composite ground
LIU Hong-kai1, 2, WU Cheng-jie1, YU Feng3, XIA Tang-dai1
1. Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China; 2. China Liaohe Petroleum Engineering Co., Ltd., Panjin 124010, China; 3. School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou 310018, China
Abstract：The traditional methods for settlement calculation of composite foundation are unable to consider the effect of load distribution of piles and soils. The differential settlement between the piles and the soils is also difficult to be predicted by these methods. This study concerns the additional stresses in tubular pile-net composite ground induced by embankment load. Based on the Mindlin’s solution, the additional stresses caused by pile end resistance, pile shaft resistances inside and outside the pipe are deduced, respectively. The Boussinesq’s solution is also used to obtain the additional stress in the soils surrounding the piles. Such improvement that incorporates the Mindlin’s and the Boussinesq’s solutions is expected to offer better prediction of the differential settlement between the piles and the soils in the tubular-pile composite ground. Finally, the new approach is applied to a case history, and the predictions seem to agree with the measurements fairly well.
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