沥青混合料三维仿真设计及虚拟剪切试验研究

Experimental Study on Three-Dimension Simulation Design and Virtual Shear Test of Asphalt Mixture

摘要:

使用凸包算法和Bubble Pack算法生成clump块体模拟粗集料颗粒，并基于PFC 5.0 3D平台实现虚拟粗集料颗粒的装配、虚拟砂浆及空隙的生成，完成沥青混合料虚拟试样的构建.最终，基于伺服控制原理进行虚拟三轴剪切试验，并对比分析室内试验及虚拟试验数据.结果表明：基于PFC 5.0 3D平台在沥青混合料虚拟试样中采用clump块体直接表征粗集料颗粒，精度可控，表面结构更加拟真；构建的沥青混合料三维离散元数值模型能够有效描述沥青混合料的力学行为.

关键词:沥青混合料;离散元法;数值模型;三轴剪切试验

Abstract:

Firstly, clumps were generated by using the convex hull algorithm and the Bubble Pack algorithm to simulate coarse aggregate particles. Then, asphalt mixture virtual samples were constructed by assembling virtual coarse aggregate particles and virtual asphalt mortars and creating voids based on the PFC 5.0 3D. Finally, the virtual triaxial shear test based on the servo control principle was carried out, and the laboratory test data and the virtual test data were compared and analyzed. The results show that based on the PFC 5.0 3D, when the clumps being used to characterize the coarse aggregate particles in the virtual sample of the asphalt mixture, not only the precision of clumps is controlled but also the surface structure characteristic is more realistic. The threedimension discrete element numerical model of asphalt mixture can effectively describe the mechanical behavior of asphalt mixture.

Key words:asphalt mixture; discrete element method; numerical model; tri-axial shear test