Steel slag was used to replace some basalt coarse aggregates in porous asphalt mixtures,and the laboratory tests and numerical simulations were conducted to investigate the fatigue performance of steel slag porous asphalt mixtures.Based on the CT scanning image,the steel slag,basalt,asphalt mortar and pores in the mixture were differentiated by threshold segmentation and imported into particle flow code(PFC)to establish discrete element model of steel slag porous asphalt mixture with particle diameter of 0.4 mm.Based on the macro-meso mechanical parameter conversion and parameter correction through virtual strength test,the virtual fatigue damage numerical simulation was carried out to obtain the specimen microcrack propagation path and fatigue life under repeated load.The results show that the virtual strength test can well fit the peak load and displacement curve of steel slag porous asphalt mixture specimens.The crack propagation path of the specimens conforms to the actual fracture situation,and the distribution of cracks mainly propagates along the internal pores of the model.The fatigue damage model can depicte the trend that the parallel bond diameter is decreased with the increasing of load cycle and decreased acceleratingly with the increasing of tensile stress between parallel bond contacts.The results of the virtual fatigue damage model are relatively close to those of laboratory fatigue damage test with an error of less than 10％,indicating that it can effectively predict the fatigue life.
关键词
钢渣/透水沥青混合料/疲劳损伤/离散元方法/裂纹扩展
Key words
steel slag/porous asphalt mixture/fatigue damage/discrete element method/crack propagation
维普
万方数据