Study on p-y models for large-diameter pile foundation based on in-situ tests of offshore wind power
WANG Wei1, YANG Jun-yi2, LIU Jian-ping2
1. Institute of Science and Technology, China Three Gorges Corporation, Beijing 100038, China; 2. China Three Gorges Renewables (Group) Co., Ltd., Beijing 100053, China
Abstract：Large steel pipe pile is the most commonly used foundation structure for offshore wind power. However, the adopted design methods for large-diameter piles are p-y models, which are originally proposed based on many small-diameter pile tests for offshore oil and gas platforms. The prediction precision of the p-y models is relatively conservative, and its reliability is not clear. Thus, a modified p-y model for clay is proposed considering the influences of pile diameter and soil layer depth. Based on the data of in-situ pile tests of offshore wind power, the accuracies of p-y models for clay and sand recommended by the API code and modified p-y model for clay to predict the lateral soil resistance, pile deformation and bending moment of laterally loaded piles are analyzed and compared. The results show that the p-y model for clay recommended by the API code significantly overestimates the soil resistance of silt-sand and clay soil, and the predicted value using the p-y model for sand is about an order of magnitude higher than the measured one. The modified p-y model for clay can precisely predict the soil resistance of silt-sand and clay soil. Based on the modified p-y model for clay and p-y model sand proposed by Sorensen, the deformation and bending moment of piles in multi-layer seabed can be precisely predicted.
王卫, 闫俊义, 刘建平. 基于海上风电试桩数据的大直径桩p-y模型研究[J]. 岩土工程学报, 2021, 43(6): 1131-1138.
WANG Wei, YANG Jun-yi, LIU Jian-ping. Study on p-y models for large-diameter pile foundation based on in-situ tests of offshore wind power. Chinese J. Geot. Eng., 2021, 43(6): 1131-1138.
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