【摘要】 岩土材料细观与宏观概念的界定有个相对尺度的区别.当前对于岩土体宏观与细观参数间规律的探索主要集中在本构关系和计算分析两个方面.论文利用颗粒流,设计了无摩擦作用下3个颗粒间黏结强度增加、弱黏结和强黏结作用下19个内摩擦角在0-90度单调增加等共计41组单轴压缩数值试验.分析发现:(1)颗粒间黏结强度的增加,使得粒间较难破裂,微裂纹数量急剧减少.(2)黏结强度一定时,45度前后破坏模式截然不同,与剪切破坏角有关.(3)强黏结峰后曲线跌落明显,脆性破坏特征明显.(4)颗粒间强度参数的变化,不改变能量转移模式,黏结强度的改变使得应变能占输入能量的比例提高,即材料破坏的塑性渐变减小.弱黏结时,随着内摩擦角的增加应变能占输入能量比例逐步减小.强黏结时,应变能占输入能量比例近似,减小不明显.更多还原

【Abstract】 There exists a relative scale in definition of microscopic and macroscopic on geo-material.Currently researches on law between microscopic and macroscopic parameters of geo-material focus on fields of constitutive equation and numerical method.In this paper,41 groups of uniaxial compression tests with three kinds of cohesion between mineral particles,nineteenth types of friction angle between mineral particles changing from 0 to 90 are designed by particle flow code.After experimental results are analyzed,found that enhancement of meso-cohesion makes particles difficult to rupture and micro-cracks decreases sharply,that failure mode changes around 45 degree under weak or strong meso-cohesion conditions,which relates to shear failure angle,that post-curve drops significantly with apparent brittleness,and that change of particle meso-strength doesn’t alter energy transferring during loading process,cohesion increase enhances proportion of strain energy and decreases plasticity of material,proportion of strain one decreases with increase of friction angle under weak cohesion condition and become constant under strong cohesion condition.更多还原