摘要
通过在屈服函数中引入材料内部长度建立应变梯度塑性增量本构关系,对岩石材料在单轴压缩条件下应变局部化的二维情况进行了研究。首先,建立了在Mises屈服准则下平面应变情况的岩石材料应变局部化带的带宽与其倾角的关系式,讨论了其带宽的分布范围和最大值与最小值形成的条件,给出岩石材料破坏Ⅰ,Ⅱ类变形的条件,并推出破坏的临界角度;其次,对岩石材料Ⅰ类变形进行了详细地分析,讨论了在不同泊松比n和lE条件下材料应变局部化带的倾角的变化范围;最后,利用所得的结论同材料破坏的库仑准则进行对比研究,对内摩擦系数给予了合理的解释。
The paper sets up plastic strain gradient plasticity increment constitutive model of rock based on adding rock's internal length parameter in the yielding function. And then, analytic expressions between the strain localization band width and its inclination angle in plane strain is presented based on von Mises' yielding criterion. Conditions of maximal value and minimal value of the strain localization band width and critical angle of rock destroy are obtained. Variation of inclination angle of the strain localization band is discussed in the difference of Poisson's ratios v and E/λ. At last, coefficient of internal friction in Coulomb-Navier criterion is explained by the strain localization band width and inclination angle.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2004年第5期694-699,共6页
Rock and Soil Mechanics
基金
辽宁省自然科学基金赞助(NO.20032144)。
关键词
应变梯度
应变梯度塑性理论
应变局部化带
Bandwidth
Compression testing
Gradient methods
Plasticity
Poisson ratio
Strain
