高模量添加剂在沥青混合料的作用机理及影响研究

Study on the Action Mechanism and Influence of a High Modulus Additives on the Asphalt Mixture

分析了添加剂对沥青混合料性能的作用机理,通过项目组制备的橡胶与硫酸钙晶须复合高模量添加剂对沥青混合料的改性,研究高模量添加剂对沥青混合料性能的影响。试验以70#沥青作为基体,采用0~3mm、3~5mm、5~15mm三档集料,高模量添加剂原料为橡胶与硫酸钙晶须。试验结果为:(1)采用高模量添加剂的沥青混合料稳定度普遍大于11k N,超过了普通胶粉改性沥青的稳定度,远远超过普通沥青8k N的稳定度;(2)采用胶粉添加剂的混合料残存强度比达到84%,而采用复合高模量添加剂的沥青混合料残留强度比达到92%;(3)采用复合高模量添加剂的沥青混合料动稳定度高达4268次/mm,明显高于胶粉改性。试验结果表明高模量添加剂的使用,明显增加了混合料的温度及水稳性能。

The action mechanism of additives to the performance of the asphalt mixture is analyzed;and through the modification of asphalt mixture with the rubber prepared by project team and calcium sulfate whisker composite additives with high modulus,the influence of the additives with high modulus on the performance of asphalt mixture is researched.In the experiment,the 70#asphalt is used as the matrix,the 3-grade aggregates of 0~3mm,3~5mm,5~15mm is adopted,and the rubber and calcium sulfate whisker is used as the high modulus additive raw materials.The results are showed as follows:(1) the stability of asphalt mixture with high modulus additives is generally greater than 11k N,which surpasses that of ordinary rubber powder modified asphalt and outdistance that of ordinary asphalt which is 8k N;(2) the residual strength ratio of the mixture with rubber powder additive reaches 84%,while the residual strength ratio of the asphalt mixture modified with composite high modulus additive is significantly improved,reaches 92%;(3) the dynamic stability of asphalt mixture modified with composite high modulus additive is up to 4268times/mm,which is obviously higher than that of rubber powder modified asphalt mixture.The experiment results indicate that the application of high modulus additives significantly increases the temperature and water stability of the mixture.