基于不同外掺物的沥青胶浆疲劳寿命分析

Analysis of Fatigue Life of Asphalt Mortar Based on Different Admixtures

通过动态剪切流变仪对70号基质沥青,以及在其基础上加入抗剥落剂、纤维、矿粉的沥青胶浆进行线粘弹性范围内的温度频率扫描试验,分析动态剪切模量随温度频率的变化规律,发现加入石灰岩矿粉的动态剪切模量有所增加,其他外掺物改变不大。通过对4种沥青胶浆进行低温下的时间扫描试验评价其抵抗疲劳开裂能力,采用模量控制法进行疲劳寿命的对比分析,发现添加外掺物的沥青胶浆疲劳寿命均有所增长,其中掺入石灰岩矿粉的增长幅度最大,认为外掺物对基质沥青抵抗疲劳开裂有帮助。

The temperature and frequency scanning test of 70#matrix asphaltis performed and then the temperature frequency scanning test in linear viscoelastic range is also conducted to study the change law of dynamic shear modulus with temperature and frequency by adding anti-stripping agent,fiber and slag asphalt cement.It is found that the dynamic shear modulus changes with the temperature and frequency,and the dynamic shear modulus of the limestone mineral powder is increased and the other extrusions are not changed.The four kinds of asphalt cement are subjected to time scanning test at low temperature to evaluate their resistance to fatigue cracking,and the modulus control method is also used to analyze the fatigue life. It is found that the fatigue life of the asphalt mortar with the addition of extender is increased,among which,the growth rate of limestone slag is the most remarkable one,indicating that the admixture of matrix asphalt is helpful to resist fatigue cracking.