根据土石混合体的地质成因和细观结构特性,将土石混合体视为由块石、土颗粒团块和土石界面组成的三相复合地质材料。提出土石混合体计算细观计算力学概念,指出土石混合体开裂破坏的计算要综合考虑内部粗颗相块石的形态、空间分布、颗粒级配及含石量等结构特性,同时还应考虑细粒相土颗粒集合体结构和强度特性以及土石界面的发育特征。土石混合体破坏的根本原因是由块石与土体的弹性不匹配,土石界面的差异滑动造成的,破坏的实质是内部裂纹的产生、扩展、聚焦和贯通的过程。土石混合体计算细观力学要解决的问题主要是探讨介质内部细观损伤的扩展过程,寻找用于描述裂纹扩展规律的方法手段。探讨土石混合体计算细观力学的研究内容,将连续介质力学、统计损伤力学和计算力学相结合去研究土石混合体的细观尺度的变形、损伤和破坏的过程,以发展较精细的细观本构关系和模拟土石混合体细观破坏的物理机制,可以更清楚地阐明土石混合的损伤开裂机制,对防灾减灾起到一定的指导作用。
According to the geological origin and meso-structure properties of rock and soil aggregates(RSA),RSA is viewed as complicated material consisted of three partition:rock blocks,soil matrix and rock-soil interface. The calculation meso-mechanics for RSA is proposed. Cracking failure simulation for RSA,the morphology,distribution,grain composition and rock percentage of rock blocks should not only be considered,but also structure of soil aggregates and rock-soil interface be considered. The primary failure reason for RSA is the elasticity mismatch,essence of failure is the initiation,propagation,penetration of cracks. Problems to be solved using meso-mechanics to explore the meso-damage process in RSA,finding proper methods to describe evolution rule of cracking. Exploring the response of RSA to force field and environment effect,continuum mechanics,statistical damage mechanics and calculation mechanics should be integrated to analysis mesoscopic deformation,damage and cracking,and develop mesoscopic constitutive model for RSA and simulate failure mechanism for rock and soil aggregates. It can clearly clarify the meso-damage mechanism for RSA,which can provide theory assistant to disaster prevention and mitigation.