基于离散元法的多孔沥青混合料集料骨架优化研究  

Research on Optimization of Porous Asphalt Mixture A ggregate Skeleton based on Discrete Element Method

作　　者：严兵 姚波 YAN Bing;YAO Bo(Jiangsu Sutong Bridge Co.Ltd.,Nantong 226017,China;Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]江苏苏通大桥有限责任公司,南通市226017 [2]南京理工大学,南京市210094

出　　处：《公路》2025年第2期14-21,共8页Highway

基　　金：中央高校基本科研业务费专项资金项目,项目编号2023102004;国家自然科学基金项目,项目编号51208103。

摘　　要：集料骨架对多孔沥青混合料的强度、刚度和抵抗永久变形能力有重要影响。为探索骨架优化的方法,首先利用激光扫描仪采集了4组不同粒径集料的二维数字图像;然后采用离散元法对虚拟单轴贯入试验进行了仿真,并通过室内试验结果进行了验证;最后采用分级掺配法,在PFC 2D中进行最优骨架的可视化设计,并研究了粗、细集料对骨架结构强度和稳定性的影响。结果表明,通过离散元法构建不规则集料堆积模型并进行虚拟单轴贯入试验具有较好的精度;粒径大于4.75 mm的集料对骨架结构的影响比粒径小于2.36 mm的集料更显著,4.75 mm可作为多孔沥青混合料粗、细集料的分界标准;粗集料可以通过嵌挤作用形成稳定的骨架结构,而细集料形成的骨架不稳定且承载能力较弱。基于离散元法所设计出的最优骨架,可以显著提高多孔沥青混合料的抗剪性能,为级配优化提供了新的方法。The aggregate skeleton has a significant impact on the strength,stiffness and resistance to permanent deformation of porous asphalt mixture.In order to explore the optimization method of aggregate skeleton,the laser scanning technology is used to collect two-dimensional digital images of four groups of aggregates with different particle sizes.Then,the discrete element method is employed to simulate the virtual uniaxial penetration test,and the results are verified through indoor experiments.Finally,the hierarchical blending method is used to visualize the optimal skeleton design in PFC 2D.The influence of coarse and fine aggregates on the strength and stability of the skeleton structure is studied.The results indicate that good accuracy can be achieved through constructing an irregular aggregate stacking model with the discrete element method and conducting virtual uniaxial penetration tests.The influence of aggregates with a particle size greater than 4.75 mm on the skeleton structure is more significant than that of aggregates with a particle size less than 2.36 mm,and 4.75 mm can be used as the standard for coarse and fine aggregates.Coarse aggregate can form a stable skeleton structure through extrusion,while the skeleton formed by fine aggregate is unstable with weak load-bearing capacity.The optimal skeleton designed based on the discrete element method can significantly improve the shear resistance of porous asphalt mixture skeleton,providing new method for grading optimization.

关 键 词：多孔沥青混合料 集料骨架 单轴贯入试验 离散元法 优化 

分 类 号：U416.217[交通运输工程—道路与铁道工程] TU528.42[建筑科学—建筑技术科学]