CAJ | 학술논문

基于离散单元法，利用PFC2D内置Fish语言编制碎石集料双轴实验条件，结合计算机语言与PFC2D中Clump命令编制将球形单元转化为随机多边形块体单元的程序。通过对比室内大型三轴试验对数值模型进行参数标定与验证，在此基础上分析3种典型粒径碎石集料的应力-应变特性以及抗剪强度特性。结果表明，围压对集料的应力-应变特性影响明显。对于不同粒径的碎石集料而言，随着围压的增加，偏应力峰值增加而应力比减小；在本文选定的围压范围内碎石集料均呈现出先压缩最终剪胀的特性，围压越大，压缩量大，最终的剪胀越不明显；碎石集料的强度包络线为非线性，相同围压条件下的抗剪强度随着粒径的增大而增加；表征摩擦角随围压的增加而减小，相同围压下，粒径越大，表征摩擦角也越大。
기우리산단원법，이용PFC2D내치Fish어언편제쇄석집료쌍축실험조건，결합계산궤어언여PFC2D중Clump명령편제장구형단원전화위수궤다변형괴체단원적정서。통과대비실내대형삼축시험대수치모형진행삼수표정여험증，재차기출상분석3충전형립경쇄석집료적응력-응변특성이급항전강도특성。결과표명，위압대집료적응력-응변특성영향명현。대우불동립경적쇄석집료이언，수착위압적증가，편응력봉치증가이응력비감소；재본문선정적위압범위내쇄석집료균정현출선압축최종전창적특성，위압월대，압축량대，최종적전창월불명현；쇄석집료적강도포락선위비선성，상동위압조건하적항전강도수착립경적증대이증가；표정마찰각수위압적증가이감소，상동위압하，립경월대，표정마찰각야월대。
With the discrete element method(DEM ) ,biaxial compressions test conditions for crushed rock aggre-gate were established in the Fish language and the Clump logic commands in PFC 2D were incorporated into the computer language to simulate the crushed rock aggregate of irregular shapes .Compared with large-scale labo-ratory triaxial tests ,the parameters of the numerical model were calibrated and validated .The stress-deforma-tion and shearing strength of the crushed stone aggregate of three typical particle sizes were analyzed .The re-search results demonstrate as follws :The confining pressure influences the stress-strain characteristics of aggre-gate significantly ;for aggregate of different particle sizes ,along with adding of the confining pressure ,the peak deviatoric stress increases while the stress ratio decreases ;within the specified range of confining pressure initial compression and subsequent dilation are observed with the aggregate ,the higher the confining pressure ,the lar-ger the compression and the smaller the dilation ;the shear strength envelope of the aggregate is nonlinear ,under the same confining pressure ,the shear strength increases with increasing of particle sizes ;the apparent friction angle decreases with adding of the confining pressure ,under the same confining pressure ,the larger the particle size of the aggregate ,the larger the apparent friction angle .