粗集料磨耗的虚拟试验分析

Virtual Test Analysis of Coarse Aggregate Abrasion

针对道路工程中广泛应用的粗集料洛杉矶磨耗试验,采用离散单元法对影响磨耗损失的重要因素进行了分析。依据能量跟踪的方法,以三维颗粒流程序PFC3D为平台,二次开发了离散球体运动分析程序,就试验条件和集料微观属性进行了讨论。研究结果表明:钢球对集料磨耗起到至关重要的作用;集料的磨耗程度与集料的属性、颗粒的碰撞能量及有效碰撞频率密切相关,颗粒主要是在钢球和集料的冲击作用下发生磨耗损失;磨耗损失程度随着颗粒接触刚度的提高而减小。

The factors that affect abrasion loss are analyzed by using the discrete element method for commonly used Los Angeles abrasion test on coarse aggregate in road engineering. Based on energy tracking method, a computer program of discrete spheres＂ movement procedure is redeveloped on the platform of 3D particle flow code （PFC3D）, with which test conditions and microscopic properties of aggregat are discussed. The results show that （1） the steel balls play a crucial role in the aggregate abrasion; （2） the abrasion degree of aggregate is closely related to the microscopic properties of aggregate, the collision energy and the effective collision frequency of particles, which is mainly contributed by the impact action of steel balls and aggregate ; （3） the abrasion degree decreases with the improvement of the particle contact stiffness.