复杂参数条件下基于空间应力解的重塑黄土沉降计算方法

Settlement Calculation Method of Remolded Loess Based on Spatial Stress Solution Under Complex Parameter Conditions

基于J.Boussinesq推出的弹性半空间在荷载作用下内部任意一点的应力分量解析式,得到任意一点土体的空间应力状态,并将其引入沉降计算模型,从而提出将围压参数引入重塑黄土沉降计算的方法。通过应力式加载三轴试验分析了重塑黄土基于偏应力、含水率、围压在内的3个参数对应变发展的影响,得到了重塑黄土在不同参数下的应变规律,提出了重塑黄土应变受多个参数影响的沉降计算公式,并通过工程实例验证了公式的可靠性。结果表明:偏应力、含水率、围压均对重塑黄土的应变有显著影响,其中偏应力、含水率均与重塑黄土的压缩变形正相关,而围压与重塑黄土的压缩变形负相关,且3个参数拟合的重塑黄土应变经验公式效果良好。通过实际工程案例验证,沉降计算结果和实际沉降监测结果基本一致,表明提出的计算方法可以更为合理且便利地应用于重塑黄土工程场地的沉降计算及分析。

Based on J.Boussinesq’s analytical formula of stress component at any point in the elastic half space under load,the spatial stress state of soil at any point was obtained and it was introduced into the settlement calculation model.A method of introducing confining pressure into the settlement calculation of remolded loess was proposed.The influence of three parameters including deviatoric stress,moisture content and confining pressure to the strain development of remolded loess was analyzed by stress loading triaxial test.The strain law of remolded lo⁃ess under different parameters was obtained,and the settlement calculation formula of remolded loess strain affected by multiple parameters was put forward.Finally,the reliability of the formula was verified by engineering examples.The results show that the deviatoric stress,mois⁃ture content and confining pressure have a significant effect on the strain of remolded loess.The deviatoric stress and moisture content are pos⁃itively correlated with the compressive deformation of remolded loess,while the confining pressure is negatively correlated with the compres⁃sive deformation of remolded loess.The empirical formula of remolded loess strain fitted by three parameters is effective.Through the engi⁃neering case verification of Shanxi Lyuliang Airport,the model settlement calculation results are basically consistent with the actual settlement monitoring results,indicating that the model in this paper can be more reasonably and conveniently applied to the settlement calculation and analysis of the remolded loess engineering site.