为了研究沥青混合料内部颗粒间力链的演化及分布规律,以AC-13沥青混合料作为研究对象,利用离散元方法重构沥青混合料数字试件,模拟简单性能试验,提取试件内部颗粒间的力链信息进行力链演化、概率分布和角度分布分析.结果表明,通过比较预测结果和实测结果,基于离散元方法重构的AC-13沥青混合料细观模型用于模拟其细观力学特性是可行的.试件内部力链空间分布具有各向异性,以垂直方向的压力力链为主,承受大部分的半正弦荷载.法向力链概率分布随加载时间的变化规律基本一致,法向接触力与平均法向接触力比值f最小时,概率分布出现最大值,f=1.75时,概率分布再次达到峰值,然后逐渐减小并趋于稳定.法向力链角度分布主要位于90°和270°附近,第一、二象限的角度分布比例远大于第三、四象限,60～120°、30～150°中法向力链角度分布比例均大于70％,最小为72.733％.%AC-13 asphalt mixture was taken as the research object to investigate the evolution and distribution laws of force chains inside the asphalt mixture.A digital specimen of AC-13 asphalt mixture was reconstructed using the discrete element method (DEM) to simulate the simple performance test (SPT).Next,the force chain information among aggregate particles was extracted to analyze the evolution,probability distribution and angle distribution of force chains.The results indicated that the AC-13 mesoscopic model reconstructed using the discrete element method was feasible to simulate the mesoscopic mechanical properties of asphalt mixture by comparing the predicted results and laboratory test results.The spatial distributions of force chains are anisotropic,which were mainly the compressed force chains in vertical direction and sustained most of the Haversine loading.The probability distributions of normal force chains which varied with loading time were consistent.The probability distribution had the maximum value at the minimum f (the ratio of normal contact force and mean normal contact force).At f=1.75,it appeared the peak value again,then gradually decreased and tended to be stable.In addition,the angle distributions of normal force chains mainly located near 90° and 270°,the angle distribution proportions in the first and second quadrant were much larger than those in the third and fourth quadrant.Also,the angle distribution proportions in 60-120° and 30-150° were both larger than 70％ with the minimum value of 72.733％.
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