加载速率对岩石材料力学行为的影响  

INFLUENCES OF LOADING RATES ON MECHANICAL BEHAVIORS OF ROCK MATERIALS

作　　者：尹小涛[1,2] 葛修润[1] 李春光[1] 王水林[1] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071 [2]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《岩石力学与工程学报》2010年第A01期2610-2615,共6页Chinese Journal of Rock Mechanics and Engineering

基　　金：冻土工程国家重点实验室开放课题资助(SKLFSE200602);国家科技支撑计划重点课题资助项目(2006BAK30B02)

摘　　要：加载速率会造成岩石材料破坏形态的改变,材料破坏过程中存在塑性向脆性转变的临界速率。在颗粒流程序下,通过Fish语言编程,虚拟实现岩石数值试件,并进行0.0005,0.0010,0.0050,0.0500m/s四个加载速率下的单轴压缩数值试验。分析加载速率对岩石破裂形态、裂纹数量和扩展、应力-应变曲线和能量转换的影响。发现:加载速率的增加破坏优势剪切带的发展,使得剪切带等速发展,材料呈现锥形破坏;加载速率的增加使得材料的力学性能表现出极大的伪增强,材料更破碎,能量损失增大,这与材料吸收和破坏消散能量的能力有关。Loading rates can result in the change of rock＇s rupture shape. There is a critical velocity during the breakage process of material when plasticity transferring to brittleness. The numerical sample of rock is virtually performed by compiling program through embedded Fish language under particle flow code condition. Then, uniaixal compression tests with four kinds of loading rates, i.e. 0.000 5, 0.001 0, 0.005 0, 0.050 0m/s, are designed to study the loading rate effect. Moreover, the influences of rupture process, crack number and propagation, stress-strain curve, stress and strain, energy transformation done by loading rate are analyzed based on these tests. It is found that increase of loading rate ruins the advantageous shear zone＇s development, which makes the shear zone expanding with same velocity; and the material failure surface appears cone shape, in which the loading rate enhances the mechanical and deformation features of material at meso-scale, which makes the rock breaking into pieces; and that the rate causes energy loss increasingly, which is relevant to the ability of absorbing and dissipating energy from its mechanical behaviors.

关 键 词：岩石力学 颗粒流 加载速率 破坏形态 裂纹 能量 

分 类 号：TU452[建筑科学—岩土工程]