基于流变学的复合改性橡胶沥青黏弹特性研究

基于流变学理论评价复合改性橡胶沥青的黏弹特性，采用动态剪切流变仪分别对基质沥青、改性沥青、不同添加剂下的复合改性橡胶沥青、干法橡胶颗粒及工厂化橡胶沥青进行滞回环试验，从残余变形、弹性贮能、耗散能、弹性比例和复合弹性模量等指标进行评价改性剂对橡胶沥青的复合改性作用及黏弹性能影响，并对试样进行应变扫描、温度扫描、频率扫描和时间扫描等常规动态剪切流变试验。结果表明:在高温条件下，复合改性橡胶沥青性能明显优于基质沥青和改性沥青；不同改性剂对橡胶沥青复合改性明显，其中PE改性剂可以提高橡胶沥青的抗永久变形能力，但是抗疲劳特性较差，岩沥青可以增加橡胶沥青的刚度、黏性流动和抗疲劳性能；脱硫胶粉与改性剂的溶胀作用明显；工厂化橡胶沥青和干法橡胶颗粒的抗疲劳特性明显，应根据不同应用场合的需求对橡胶沥青进行复合改性。

Study on viscoelastic properties of rubber modified asphalt based on rheology

In this study, viscoelastic properties of rubber modified asphalt were evaluated based on the rheological theory. Using dynamic shear rheometer, the matrix asphalt, modified asphalt, rubber modified asphalt with different additives, dry rubber particles and industrialized rubber asphalt were tested, respectively, for their hysteresis loops. Based on the indices such as the residual deformation, elastic energy-storage, elastic ratio and composite elastic modulus,the effects of modifying agent on the modification and viscoelastic properties of rubber asphalt were analyzed, and then, the conventional dynamic shear rheological tests were conducted on the samples for four types of scanning, namely strain scanning, temperature scanning, frequency scanning and time scanning. The results show that the properties of rubber modified asphalt are better than those of the matrix asphalt and the modified asphalt under high temperature; different modifying agents have significantly different effects on the modification of composited rubber asphalt, and among the modifying agents, the PE agent can improve the permanent deformation resistance of asphalt rubber, but its fatigue resistance is poor; the rock asphalt can increase the stiffness, viscous flow and fatigue resistance of rubber asphalt,; the swelling effects of desulfurization rubble powder and modifying agents are remarkable; The fatigue properties of industrialized rubber asphalt and dry rubber particles  are obvious, and hence, rubber asphalt shall be composited and modified according to the needs in different application cases.