基于Geddes解的取土器贯入引起的土体附加应力分析.docVIP

基于Geddes解取土器贯入引起的附加应力 吴跃东罗如平 （1. 210098； 2. 河海大学岩土工程科学研究所，江苏 南京 210098） 摘要：为了研究取土器贯入引起的附加应力分布特性基于Geddes应力解得到了取土器管内任意一点处土样由于引起的竖向附加应力解，并通过数值方法对引起的管内土体附加竖向应力分布特性及取土器参数对其影响进行了分析。计算结果表明：端阻力的作用会引起土体产生一个由压应力转变为拉应力的过程，且其拉压应力不随取土器直径变化而变化增大取土器的直径能有效减少端阻力及侧壁摩阻力引起的轴线处土体的附加应力，考虑两者的共同作用，大直径取土器能较为明显的提高取土样的质量。 关键词：取土扰动；附加应力；Geddes应力解；端阻力；侧摩阻力 中图分类号：TU 431 文献标识码：AThe Analysis of Additional Stress Induced by Sampler Penetration Based on Geddes Solution Wu Yuedong1,2，1，Luo Ruping1 （Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China 2、Geotechnical Research Institute, Hohai University, Nanjing 210098, China） Abstract: In order toobtain the solution of the additional stress induced by sampler penetration, based on the Geddes solution ,this paper obtained the solution of the additional stress of soils induced by the end resistance and the side resistance, then the additional stress distribution characteristics of soils and the influence from the sampler’s parameters was analyzed by numerical integration. The calculation results show that: during the sampler penetration, the effects of end resistance will cause a process in which compressive stress changes into tensile stress, and the tensile stress dose not vary with soil sampler diameter and penetration depth; increasing the diameter of the soil sampler can reduce end resistance and the additional stress of soil on the axis induced by side resistance effectively, considering the effects of both together, larger diameter soil sampler can obviously improve the quality of sample. Key words: sampling disturbance; additional stress; Geddes’s solution; end resistance; side resistance 基金项目：国家自然科学基金（2014B04914）作者简介：吴跃东（1969-），男，福建云霄人，副教授，博士，主要从事岩土工程测试及软土地基处理研究 E-mail: hhuwyd@163.com 在岩土工程勘察设计当中土样物理力学参数的确定是一项最为基础性的工作，土样参数的准确与否直接关系到了工程设计的好坏。然而在取土操作的各个环节中会不可避免的引起土样的扰动，土样的物理力学性质发生较大改变其中取土器贯入土体引起的附加应力就是一个重要。对于取土器贯入土体引起的附加扰动分析，国内外学者进行了一