基于桩周土体固结的静压桩承载力时效性研究  

Study on time effect of bearing capacity of jacked pile based on soil consolidation

作　　者：刘时鹏[1] 施建勇[2] 张金水 张兴胜[1] LIU Shipeng SHI Jianyong ZHANG Jinshui ZHANG Xingsheng(College of Resources and Environment, North China University of Water Resources and Electric Power, Zhengzhou 450011, China Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education, Geotechnical Research Institute, Hohai University, Nanjing 210098, China Xiaolangdi Project Construction ＆ Management Center, Ministry of Water Resources, Zhengzhou 450099, China)

机构地区：[1]华北水利水电大学资源与环境学院,河南郑州450011 [2]河海大学岩土力学与堤坝工程教育部重点实验室,岩土工程科学研究所,江苏南京210098 [3]水利部小浪底水利枢纽管理中心,河南郑州450099

出　　处：《中南大学学报（自然科学版）》2016年第10期3454-3460,共7页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(50878075);华北水利水电大学高层次人才科研启动项目(201406)~~

摘　　要：基于静止土压力系数K_0固结饱和原状土体超静孔隙水压力消散的解析解,根据沉入低渗透性饱和土体中静压桩承载力与超静孔隙水压力消散程度的相关性,得到其在沉桩后不同休止时期极限承载力的理论解,实现静压桩在任意休止时间承载力的预测。与其他解不同,该理论解采用更符合天然土体实际工作性状的K_0固结土体弹塑性模型,能够考虑不等向固结和应力等多种因素影响,并同时考虑桩侧和桩端土体固结对静压桩承载力时效性的贡献。工程实例分析结果表明:沉桩施工所产生的超静孔隙水压力、不同时间的消散值以及不同休止时间承载力的实测值与理论值较吻合,证明解的合理性。Based on the dissipation solution of excess pore water pressure in K_0 consolidated saturated soils, the correlation between the dissipation degree of excess pore water pressure and the bearing capacity of jacked pile driven in low permeability saturated soils, a theoretical solution which can predict ultimate bearing capacity of jacked pile at arbitrary inactivity time was obtained. Different from other solutions, the K_0 consolidated soil elastoplastic model which considers actual characteristics of natural soil, anisotropic consolidation, stress history, consolidation of pile side and pile end soil were used in the new theoretical solution. The engineering example results indicate that the analytical solutions of pore water pressure and bearing capacity at inactivity time are in good agreement with the in-situ measured values. The rationality of the solutions is verified.

关 键 词：静压桩 K0固结土体弹塑性模型 超静孔隙水压力 固结 承载力时效性 

分 类 号：TU46[建筑科学—结构工程]