CAJ | 학술논문

　　考虑到颗粒流（PFC ）表示的颗粒速度场和位移场并不能很直观地表示出颗粒材料在加载破坏中的变形特征，从宏观的角度引入易于理解和接受的颗粒集合体的有效应变定义，建立了考虑不同周围压力、颗粒粒径、粗糙程度、接触刚度等因素在内的颗粒材料数值模型，并结合一定的初边值条件，编制了相应的 Fish语言程序。将细观数值分析与宏观表示相结合，分析了双轴压缩试验中颗粒材料变形破坏的规律和各种基本的细、宏观影响因素。数值结果表明，基于宏观连续体概念的有效应变充分显示了颗粒材料变形破坏的发展形成过程及相关特征：破坏区域完全形成于应力‐应变曲线峰值之后的软化阶段，域内有较大的孔隙，域中的颗粒显示出明显的颗粒旋转；颗粒的法向与切向刚度、粗糙程度、颗粒集合体试样所受的压力水平，以及颗粒粒径等对颗粒材料的承载能力，破坏区域的形成、型式与厚度等有一定的影响。
　　고필도과립류（PFC ）표시적과립속도장화위이장병불능흔직관지표시출과립재료재가재파배중적변형특정，종굉관적각도인입역우리해화접수적과립집합체적유효응변정의，건립료고필불동주위압력、과립립경、조조정도、접촉강도등인소재내적과립재료수치모형，병결합일정적초변치조건，편제료상응적 Fish어언정서。장세관수치분석여굉관표시상결합，분석료쌍축압축시험중과립재료변형파배적규률화각충기본적세、굉관영향인소。수치결과표명，기우굉관련속체개념적유효응변충분현시료과립재료변형파배적발전형성과정급상관특정：파배구역완전형성우응력‐응변곡선봉치지후적연화계단，역내유교대적공극，역중적과립현시출명현적과립선전；과립적법향여절향강도、조조정도、과립집합체시양소수적압력수평，이급과립립경등대과립재료적승재능력，파배구역적형성、형식여후도등유일정적영향。
In view of the inability of velocity field and displacement field in partical flow code (PFC) simulation in showing the characteristics of localization during loading and subsequent failure intuitionisticly , the definition of effective strain in macro‐scope is introduced into the granular materials ,w hich is easy to be understood and accepted . T he numerical models including different confining pressures , granular diameters , frictional coefficients and stiffness coefficients are established ,and then programmed with Fish language for granular materials under certain initial and boundary conditions .Combining the numerical tests of PFC with expression of the effective strain in macro‐scope ,the rules and influencing factors for the formation of failure bands during biaxial tests are analyzed .The numerical results indicate that the effective strain in macro‐scope is able to exhibit the development process and relevant characteristics of deformation and failure for granular materials :the entire failure bands are formed after the peak value and during the softening stage of the stress‐strain curve ,and bigger voids and more obvious rotation of granules appear in failure bands than in other parts . It is also show n that the normal and tangent stiffness coefficients of granules , the frictional coefficients between granules ,the confining pressures around the two sides of the sample , and the diameters of granules affect the formation ,types and thickness of failure bands for granular materials to some degree .