橡胶粉复合改性沥青在应力吸收层的应用研究

Study on Application of Crumb Rubber Composite Modified Asphalt in Stress Absorbing Layer

反射裂缝应力吸收层系统由高弹性不透水的热沥青中面层和推荐使用的SBS改性热拌沥青罩面层构成,中面层采用聚合物改性沥青粘结料,沥青含量高,混合料中细骨料比重大.而目前使用SBS生产的改性沥青成本较高,在这个情况下,茂名沥青储运中心和同济大学合作,通过分析研究,针对目前SBS改性沥青存在的成本高、橡胶粉沥青指标较差的问题,确立了橡胶粉、SBS高分子改性剂相结合的复合试验方法;通过不同的配合比试验和沥青性能试验,确定橡胶粉的最佳掺量为15%,SBS的最佳掺量为5%,实验结果表明,橡胶粉复合改性沥青PG分级可以达到PG76-34,软化点大于85度,老化前5度延度大于60 cm,老化后5度延度大于40 cm.橡胶粉复合改性沥青性能优越,可以变废为宝,节约生产成本,符合绿色、环保、低碳的发展理念.

The use of the surface layer and the recommended heat reflected crack of asphalt stress absorbing layer by high elastic waterproof SBS in modified hot mix asphalt overlay layer, surface layer using polymer modified asphalt binder, asphalt mixture, high content of fine aggregate than the major. At present the use of SBS modified asphalt production cost is high. In this case, the Maoming asphalt storage and transportation center works with the Tongji University cooperation. Through analysis and research, aiming at the problems of SBS modified asphalt with high cost, rubber powder asphalt index, the composite test method of rubber powder, SBS polymer modifier combination has been sot. Through the different asphalt mix ratio test and performance test, we determine the optimal dosage of rubber powder is 15% and the optimal dosage of SBS is 5%, the experimental results show that the rubber powder modified asphalt PG grade can reach PG76-34, the softening point is greater than 85 degrees, 5 degrees before aging ductility is greater than 60 cm, aged 5 the degree of ductility is greater than 40 cm. Rubber powder composite modified asphalt has superior performance, which can be changed into waste materials and save production costs. It conforms to the green, environmental protection and low carbon development concept.