CAJ | 학술논문

采用PFC3D数值模拟软件，研究散粒体材料在真三轴试验条件下中主应力对强度和变形的影响，并用统计方法从细观角度探讨中主应力的影响机制。数值模拟结果表明，中主应力比b增大，材料的有效内摩擦角、轴向应力峰值以及对应的轴向应变都呈现先增大然后减小的变化规律。b值的增大使中主应力方向应变由拉伸变为压缩，体应变由剪缩变为剪胀。b值对散粒体材料有效内摩擦角的影响规律和Lade-Duncan准则比较一致。从细观层面上， b值影响颗粒间法向接触力的分布。在b值增大过程中，当b值较小时中主应力方向的增强效应占主导使得材料强度增大，b值较大时小主应力方向的减弱效应占主导使得材料强度降低。
채용PFC3D수치모의연건，연구산립체재료재진삼축시험조건하중주응력대강도화변형적영향，병용통계방법종세관각도탐토중주응력적영향궤제。수치모의결과표명，중주응력비b증대，재료적유효내마찰각、축향응력봉치이급대응적축향응변도정현선증대연후감소적변화규률。b치적증대사중주응력방향응변유랍신변위압축，체응변유전축변위전창。b치대산립체재료유효내마찰각적영향규률화Lade-Duncan준칙비교일치。종세관층면상， b치영향과립간법향접촉력적분포。재b치증대과정중，당b치교소시중주응력방향적증강효응점주도사득재료강도증대，b치교대시소주응력방향적감약효응점주도사득재료강도강저。
Using PFC3D,the influence of intermediate principal stress on strength and deformation of granular materials was studied and microcosmic mechanism was probed using statistical method. Simulating results show that shearing resistance angle,axial peak stress and the corresponding axial strain firstly increase and subsequently decrease with the increase of intermediate principal stress ratiob. The strain in the intermediate principal stress direction is tensile train and becomes compressive strain with the increase ofb,while volumetric strain transitions from shear contraction to shear dilatancy. Simulating results agree very well with Lade-Duncan criterion. In microscopic level,b affects the distribution of contact forces. Asb increases,the increase effects in intermediate principal direction are more prominent for lowerb values and strength has an initial increase. Whenb approaches 1,the decrease effects in minor principal direction are more prominent and lead to a lower strength.