基于"过剩砂浆"理论,采用一种显示求解的数值分析方法即离散元法(discrete element method,DEM),按照真实的粗骨料级配,利用平行粘结模型对自密实混凝土工作性能进行数值模拟.结合坍落度扩展试验和J型环试验的结果,运用粒子群-神经网络算法进行关键参数反演,以获得精确的模型细观参数.为了进一步验证该方法的科学性,对自密实混凝土的L型箱试验进行离散元数值模拟,并与室内试验获得的流动时间和表面流动形态进行了对比分析,结果表明:流动时间的模拟值和试验值平均误差为7%,SCC最终流动形态的模拟结果和试验结果吻合较好,表明建立的离散元模型和反演的参数能够精准地模拟SCC的工作性能,运用DEM方法研究SCC的工作性能是可行的
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