废旧胶粉沥青最优性能制备研究

Experimental study on the optimal performance preparation method of waste rubber powder asphalt

选择壳牌90#基质沥青和废旧轮胎胶粉为主要试验原料,以沥青针入度、黏度、延度、软化点作为评价橡胶沥青性能的指标,对橡胶沥青的制备温度、胶粉剂量、胶粉目数、搅拌方式、热存储方式、热存储时间、微观结构进行了深入的研究。结果表明:制备温度对橡胶沥青的影响较为复杂;当胶粉目数小于30和胶粉掺量小于20%时,剪切法生产方式的沥青针入度大于搅拌法;在不同胶粉目数和不同胶粉掺量情况下,采用搅拌法生产的沥青软化点大于剪切法,采用搅拌法生产的沥青粘度大于剪切法;橡胶沥青的粘度在静态存储情况下,其下降速率远大于动态存储方式。最后得出:在185℃的制备温度下搅拌加工1 h进行生产,在静态热存储条件下存储时间不超过2 h,制备好的沥青最多可再重复加热1次,生产的橡胶粉沥青的延度、粘度、针入度、软化点等各项技术指标性能最优。

Shell 90#base asphalt and waste tire rubber powder are selected as the main test materials,and the penetration,viscosity,ductility and softening point of asphalt are taken as the indicators to evaluate the performance of rubber asphalt.The preparation temperature,rubber powder dosage,rubber powder mesh,mixing mode,heat storage mode,heat storage time and microstructure of rubber asphalt are studied in depth.The results show that the influence of preparation temperature on rubber asphalt is complex;when the mesh number of rubber powder is less than 30 and the content of rubber powder is less than 20%,the penetration of asphalt produced by shear method is greater than that by mixing method;the softening point of asphalt produced by mixing method is higher than that of asphalt produced by shear method,and the viscosity of asphalt produced by mixing method is higher than that of asphalt produced by shear method under the conditions of different rubber powder mesh and different rubber powder content;the viscosity of rubber asphalt in static storage is much faster than that in dynamic storage.Finally,it is concluded that the prepared asphalt can be reheated for up to one time at the preparation temperature of 185℃after mixing for 1 h,and the storage time under the static hot storage condition is not more than 2 h.The produced rubber powder asphalt has the best performance in terms of ductility,viscosity,penetration,softening point and other technical indicators.