不同粒径对粗粒土力学参数影响的研究

Influence of particle size on mechanical parameters of coarse grain soil

粗颗粒土作为良好的填筑材料广泛应用于高填方工程。然而,由于粗颗粒土粒径范围较广,其力学性质的影响因素复杂,不同的研究人员因为研究对象的特殊性可能得出不同的结论。针对4组不同粒径和尺寸,但每一组均由相同粒径的颗粒生成的试样,用离散元软件开展了三轴试验模拟。模拟结果验证了一般性的室内三轴试验结果,并且从细观上解释了剪胀与剪缩试验现象,讨论了不同粒径对粗粒土宏观力学参数的影响。指出离散元模拟时细观参数取值与颗粒粒径呈正比例相关,并通过室内三轴压缩实验验证了该结论。

As a good filling material,the coarse grain soil is widely used in high-filling engineering. However,the influential factors for mechanical parameters of coarse grain soil are complicate due to the wide range of particle？ size,so different researchers draw various conclusions. Four group samples of different sizes and particles were adopted to carry out triaxial test simulations with a discrete element software,and the particle size of each group was the same. The simulation results verified the general conclusions of indoor triaxial tests,and explained the experiment phenomenon of dilatancy and the shear shrinkage from？ a？ micro？ perspective. We research the influence of different particle size on the macroscopic mechanics parameters of coarse grain soil and propose that the microscopic parameters in a discrete element simulation are positively related to the particle size,and this conclusion is verified through indoor triaxial compression tests.