岩土颗粒三维形状表征参数对比分析

岩土混合介质中骨架颗粒的形状尺寸对介质力学性质具有不同影响,基于典型岩土颗粒(卵石、碎石)的三维激光扫描数据,通过球谐函数对颗粒的形状表征参数进行了统计分析,探讨了各统计量之间的影响变化.结果表明:对相同体积碎石和卵石而言,体积越小则卵石和碎石的表面积差距越小,所产生的力学性质影响区别越小;卵石的整体形状系数要普遍高于碎石;棱角度和球形度服从一定程度上的线性分布,并且球形度和棱角度呈反比关系;颗粒体积越大则颗粒表面的细节体现得越明显,表面的细节对相关力学性质有着重要影响,形状系数可以在一定程度上反映颗粒的磨圆程度.研究结果可为岩土颗粒在宏观性质中的相互力学作用分析提供借鉴.

Comparative analysis for 3D shape characterization parameters of rock and soil particles

The size and shape of skeleton particles in the mixed rock and soil medium have different influence on the mechanical properties of the medium. Based on the 3D laser scanning data of typical geotechnical particles including the pebbles and gravels, the statistical analysis on the shape characterization parameters of the particles was performed with the spheric harmonic function, and the influence change among various statistical magnitudes was dicussed. The results show that for the gravels and pebbles with the same volume, the smaller the volume is, the smaller the difference in the surface area of gravels and pebbles is, and the smaller the influencing area for the mechanical properties is. The overall shape coefficient of pebbles is greater than that of gravels. In addition, the edge degree and sphericity obey a certain linear rule, and share an inverse relationship with each other. The bigger the size of particles is, the obvious the detail exhibition of the particle surfaces is. Furthermore, the details of the surfaces have important influence on the relevant mechanical properties. The shape coefficient can reflect the sphericity degree of the particles to a certain extent. The study results can provide the references for the macroscopic role analysis of rock and soil particles in the relevant mechanical properties.