摘要
颗粒破碎是自然界中常见的物理现象。高应力水平作用下堆石坝料会发生严重的颗粒破碎。基于热力学和微极理论,建立了考虑颗粒破碎的微观力学模型。为了模拟颗粒体的破碎过程和侧向应力的影响,把胶结在一起的3个等粒径的颗粒体当作颗粒破碎体。通过引入颗粒破碎准则,并采用均匀化理论,建立了颗粒尺度的应力–应变关系,并模拟了加载过程中颗粒破碎发生时的应力和应变。计算结果表明所提出的微观力学模型可以模拟颗粒破碎前的应力逐渐增大和破碎时的应力跌落现象。
Grain breakage is a common physical phenomenon in nature. Rockfill materials may break up seriously upon high stress level of loading. Based on the thermomechanics and micropolar theory, a micromechanical model for granular matter is formulated considering the grain breakage. Three grains with the same radius bonded together are taken as an assembly of crushing grain to simulate the grain breaking process with the influence of lateral stress. By introducing the grain breakage criterion and using the homogenization theory, the stress-strain relationship in particle scale is established, and the stress and strain are modeled with breakage occurring in the process of loading. The computed results demonstrate that the proposed micromechanical model can simulate the increase of stress before grain breakage and stress dropping at occurrence of grain breakage.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2015年第2期276-283,共8页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(91215301)
关键词
热力学
微极理论
颗粒破碎
微观力学
破碎准则
thermo-mechanics
micropolar theory
grain breakage
micromechanics
breakage criterion
