南京地铁地基黏土物理力学参数相关性试验研究

通过大量的土工试验,对南京地铁地基黏土物理力学参数间的相关关系,特别是黏聚力、压缩模量、液性指数等与含水量、密度、孔隙比、标贯击数等的相关关系进行研究,并给出相应的数学回归方程式和相关系数。结果表明:南京地铁地基黏土的密度、孔隙比、压缩模量、压缩系数、液性指数、导热系数等物理力学参数与黏土含水量之间的线性相关程度好,相关系数达0.928以上,平均为0.975 7;黏土的压缩模量、黏聚力、导热系数随黏土的密度增大而增大,压缩系数随黏土的密度增大而减小,且这4个参数与密度的线性相关程度很好,相关系数达0.93以上,平均为0.953 5;压缩模量、黏聚力、液性指数、导热系数等与孔隙比的线性相关程度也较好,相关系数达0.89以上,平均为0.941 835;孔隙比、压缩系数、液性指数、内摩擦角、黏聚力、压缩模量、导热系数、标贯击数的线性相关程度很好,相关系数达0.947以上,平均为0.973 53。

Experimental Study on the Correlativity between the Physical and Mechanical Parameters of Foundation Clay in Nanjing Subway Engineering

Through large numbers of geotechnical engineering tests,the correlativity between the physical and mechanical parameters of foundation clay in Nanjing Metro is studied,particularly between the cohesive force,compressive modulus,liquidity index,etc.and water content,density,void ratio,the blow count of standard penetration test(SPT),etc.Corresponding mathematical regression equations and correlativity coefficients are given.Results show that the physical and mechanical parameters of foundation clay in Nanjing Metro engineering,such as density,void ratio,compressive modulus,compressive coefficient,liquid index and thermal conductivity coefficient,etc are in good linear correlativity with the water content of clay.The correlativity coefficient is larger than 0.928,and the average value is 0.975 7.The compressive modulus,cohesive force and thermal conductivity coefficient of clay increase along with the increase of clay density.The compressive coefficient decreases with the increase of clay density.These 4 parameters are in good linear correlativity with density.The correlativity coefficient is over 0.93,and the average value is 0.953 5.The compressive modulus,cohesive force,liquid index and thermal conductivity coefficient,etc.are also in good linear correlativity with void ratio.The correlativity coefficient is over 0.89,and the average value is 0.941 835.Void ratio,compressive coefficient,liquid index,inner friction angle,cohesive force,compressive modulus and thermal conductivity coefficient are in good linear correlativity with the blow count of SPT.The correlativity coefficient is over 0.947,and the average value is 0.973 53.