摘要
近海风电基础结构以大直径钢管桩为主,然而采用的设计方法仍是基于海上油气平台小直径桩试桩试验总结提出的p–y模型,其预测结果相对保守,可靠性值得商榷。鉴于此,提出一种综合考虑桩径和地层深度影响的黏土p–y修正模型,基于海上风电原位试桩数据对比分析API规范推荐的黏土p–y模型和砂土p–y模型,以及黏土p–y修正模型对水平受荷桩的桩侧土体抗力、桩身变形和桩身弯矩预测的准确性。研究结果表明:API规范推荐的黏土p–y模型显著高估了淤泥混砂和黏土的桩周土体抗力,砂土p–y模型的预测值比实测值约高一个数量级;黏土p–y修正模型对淤泥混砂和黏土的桩侧土体抗力有很好的预测性;基于黏土p–y修正模型和Sorensen等提出的砂土p–y模型能够较精准地预测海床地基中的桩身变形和桩身弯矩。
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.
作者
王卫
闫俊义
刘建平
WANG Wei;YANG Jun-yi;LIU Jian-ping(Institute of Science and Technology,China Three Gorges Corporation,Beijing 100038,China;China Three Gorges Renewables(Group)Co.,Ltd.,Beijing 100053,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2021年第6期1131-1138,共8页
Chinese Journal of Geotechnical Engineering
基金
清华大学水沙科学与水利水电工程国家重点实验室开放基金项目(sklhse-2020-C-06)
中国长江三峡集团有限公司科研项目(WWKY-2020-0735)。
