新型平台桩靴在“砂-黏”地层中穿刺的数值模拟研究  

Prediction of peak resistance for a new type of spudcan through sand overlying clay

作　　者：孔秋平 刘炎 郑敬宾 王栋 罗承浩 郭琼玲 KONG Qiuping;LIU Yan;ZHENG Jingbin;WANG Dong;LUO Chenghao;GUO Qiongling(Fujian Yon King Geotechnical Co.,Ltd.,Longyan 361000,China;Institute of Marine Geotechnical Engineering,College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China)

机构地区：[1]福建永强岩土股份有限公司,福建龙岩361000 [2]中国海洋大学环境科学与工程学院海洋岩土工程研究所,山东青岛266100

出　　处：《海洋工程》2023年第1期20-28,共9页The Ocean Engineering

基　　金：福建省科技计划资助项目(2020I1011);国家自然科学基金资助项目(42172294,U1806230,51809247)。

摘　　要：开发了一种新型平台桩靴,可通过活动板转动实现自升式平台不同阶段桩靴受力面积的灵活变化。基于大变形有限元方法,模拟新型桩靴基础在“砂-黏”地层中的贯入过程,分析了活动板转角、砂层厚度比、摩擦角和黏土层不排水抗剪强度对新型桩靴贯入阻力的影响,并与普通桩靴的贯入响应比较。数值分析中,上覆砂土和下层黏土分别采用摩尔库伦模型和修正Tresca模型进行模拟。结果表明:新型桩靴穿刺时,土层参数对峰值阻力的影响规律与普通桩靴相同,但其峰值阻力随活动板转角的变化而变化,无法直接使用具有等效面积普通桩靴的穿刺预测方法。考虑各项关键影响因素,结合穿刺破坏时的地基破坏模式,基于数值模拟结果提出了适用于新型桩靴的贯入阻力预测公式。A new type of spudcan was invented by Fujian Yon King Geotechnical Co.,Ltd.The new spudcan is able to change its bearing area at different stages through foldable boards attached to its four sides.Based on a large deformation finite element approach,numerical simulation of the new spudcan penetrating through sand overlying clay was performed to explore the effects of board angle,sand layer thickness ratio,internal friction angle and clay undrained shear strength on the penetration resistance of spudcan.The results were compared with the penetration response of the generic spudcan.The sand layer and the clay layer were modelled by the Mohr-Coulomb model and modified Tresca model,respectively.The results provide insights that the effects of soil parameters on the peak resistance of new spudcan are similar to the generic spudcan.However,the peak resistance in the sand layer is dependent on the board angle of the new spudcan,and hence the existing predictive methods for a generic spudcan with the equivalent area are not applicable to the new spudcan.Based on the numerical results,an improved mechanism-based design approach for predicting the peak resistance of the new spudcan is proposed to account for the key influential factors.

关 键 词：桩靴 大变形有限元 穿刺 自升式平台 贯入阻力 黏土层 

分 类 号：P751[交通运输工程—港口、海岸及近海工程]