基于多种路用环境下对布敦岩沥青混凝土低温开裂特性的分析  

Analysis on Low Temperature Cracking Characteristics of Buton RockAsphalt Concrete under Various Road Conditions

作　　者：闫景晨[1] 陈秀楠 马炎沛 YAN Jingchen;CHEN Xiunan;MA Yanpei(School of Civil Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Southwest Branch of China Construction 7th Engineering Bureau Co.,Ltd,Chongqing 400000,China)

机构地区：[1]内蒙古工业大学土木工程学院,内蒙古呼和浩特010051 [2]中国第七工程局有限公司西南分公司工程部,重庆400000

出　　处：《材料科学与工程学报》2023年第3期514-521,共8页Journal of Materials Science and Engineering

摘　　要：本研究通过冻断试验和三点弯试验分别对五种路用环境下的布敦岩沥青混凝土、基质沥青混凝土和SBS改性沥青混凝土进行低温抗裂对比分析,并通过数值模拟试验从试件损伤和能量耗散两方面进行布敦岩沥青混凝土低温开裂机理研究。结果表明:布敦岩沥青混凝土具有比其他两种沥青混凝土更高的转化点温度,但在冻结时的断裂强度和冻断温度略低于SBS改性沥青混凝土,而优于基质沥青混凝土。在低温下,布敦岩沥青混凝土的应变能密度大于基质沥青混凝土,略低于SBS改性沥青混凝土,这表明在基质沥青中掺加适量的布敦岩沥青可以提高其抗温缩开裂性能。另外,布敦岩沥青混凝土在低温条件下弯曲破坏过程中只有少部分塑性变形,应变能以塑性变形的方式耗散较少,主要是通过脆性破坏产生的裂隙耗散。This paper conducts comparative analysis on the low temperature fracture resistance of Buton rock asphalt concrete,matrix asphalt concrete and SBS modified asphalt concrete under five different road conditions using TSRST test and the three-point bending test.The low temperature cracking mechanism of Buton rock asphalt concrete was studied from two aspects using the numerical simulation,the damage of the specimen and the energy it dissipated.The results show that the temperature at the conversion point of Buton rock asphalt concrete is higher than those of the other two kinds of asphalt concrete,with a less degree of fracture at a slightly lower temperature than that of SBS modified asphalt concrete,and shows better performances than that of matrix asphalt concrete.The strain energy density of Buton rock asphalt concrete is larger than that of base asphalt concrete and slightly smaller than that of SBS modified asphalt concrete when cracking at low temperatures till the specimen is destroyed,which indicates that adding a proper amount of Butun rock asphalt to base asphalt can improve its resistance to temperature shrinkage and cracking.In addition,there is only a small part of plastic deformation in the bending and collapsing processes at low temperatures,and the strain energy is less dissipated in the way of plastic deformation,which is mainly dissipated through cracks caused by brittle failure.

关 键 词：布敦岩沥青混凝土 低温开裂 应变能密度 损伤变量 离散元 

分 类 号：U414[交通运输工程—道路与铁道工程]