玄武岩纤维复合布敦岩沥青改性沥青混凝土低温开裂特性

Low temperature cracking characteristics of asphalt concrete synergistically modified by basalt fiber and Buton rock asphalt

为了探究玄武岩纤维复合布敦岩沥青改性沥青混凝土在寒冷地区的适用性,通过小梁弯曲试验、数字图像相关(digital image correlation,DIC)技术与低温约束应力试验,对布敦岩沥青混凝土、基质沥青混凝土和玄武岩纤维复合布敦岩沥青改性沥青混凝土的低温开裂特性进行研究。结果表明:在低温条件下,玄武岩纤维复合布敦岩沥青改性沥青混凝土变形能力强,冻断温度及转化点温度低;较其他2种沥青混凝土损伤因子达到1所需的时间长,裂缝宽度小,关键开裂点出现时间晚。宏细观分析均表明,玄武岩纤维复合布敦岩沥青改性沥青混凝土的低温抗裂性能优异。

In order to study the applicability of asphalt concrete synergistically modified by basalt fiber and Buton rock asphalt in cold regions,this paper studies the low temperature cracking characteristics of Buton rock asphalt concrete,matrix asphalt concrete and basalt fiber Buton rock asphalt composite modified asphalt concrete through trabecular bending test,digital image correlation(DIC)technology and low temperature constraint stress test.The results show that under low temperature conditions,basalt fiber Buton rock asphalt composite modified asphalt concrete has strong deformation ability,low freezing temperature and conversion point temperature.Compared with the other two asphalt concrete,the time required for the damage factor to reach 1 is longer,the crack width is smaller,and the key cracking point appears later.The macro and micro analysis shows that the basalt fiber Buton rock asphalt co-modified asphalt concrete has excellent low temperature crack resistance.