砂土静力触探锥头阻力增量弹塑性解

Incremental Elastic-plastic Solutions for Cone Tip Resistance in Sand

采用SMP屈服准则以考虑中主应力对砂土强度的影响,基于从压缩机理出发的增量弹塑性计算模式和柱孔扩张理论推得极限锥头阻力和临界深度解析解。同时采用Mohr-Coulomb破坏准则和柱孔扩张理论推导了极限锥头阻力和临界深度解析解。并结合试验数据,将基于不同准则和不同孔扩张机理的解答进行了对比分析。结果表明:基于空间滑动面理论(SMP准则)和柱孔扩张机理的有关解答与试验数据拟合效果最好。

In order to include the effect of intermediate principle stress,the spatial mobilization plane（SMP） theory is adopted in this paper,based on incremental elastic-plastic model to consider both the incremental shearing dilation of sand under the large strain in the plastic area and the compressibility of sand under the small strain in outer elastic area.Together with the governing equations of the cylindrical cavity expansion,the approximate solutions for both critical depth in cone penetration tests and cone resistance below the critical are established.Meanwhile,the solutions are also obtained,which based on Mohr-coulomb failure criteria and cylindrical cavity expansion theory.By comparing the solutions from the different cavity expanding theory and the different failure criteria, the results show that the solutions based on SMP criteria and cylindrical cavity expansion theory agree best with the experimental results;the solutions based on Mohr-coulomb failure criteria and cylindrical cavity expansion theory are lower.