基于正交设计法的橡胶沥青性能试验研究

Experimental Study on Performance of Rubber Asphalt Based on Orthogonal Design Method

为提高橡胶沥青的性能,依托河北廊沧高速公路建设工程,针对当地气候特征及材料性状,借助正交试验优选橡胶沥青的9种正交组合,并研究了胶粉掺量、胶粉目数、沥青型号对橡胶沥青3大指标的规律性影响。此外,采用老化试验和布氏黏度试验,评价了拌和时间以及拌和温度对橡胶沥青老化前后性能的影响程度。研究结果表明:橡胶沥青正交试验各因素的显著性顺序为:胶粉掺量>基质沥青型号>胶粉目数;拌和时间和拌和温度对橡胶沥青老化性能影响显著,因此在制备橡胶沥青的过程中需合理控制时间和温度;选取90#、60目、胶粉含量为20%的橡胶沥青,在190℃的环境下拌和60 min,能使橡胶沥青达到最佳性能;建议橡胶沥青的性能评价指标以5℃延度和180℃黏度为主,针入度和软化点为辅。

In order to improve the performance of rubber asphalt,relying on Langfang-Cangzhou expressway construction project in Hebei Drovince,according to the regional climate characteristics and material property there,9 orthogonal combinations are selected preferably by orthogonal test,and the effect of rubber powder dosage,rubber powder mesh and asphalt type on the regularity of 3 major indexes of rubber asphalt is studied. In addition,the influences of mixing time and mixing temperature on the performance of rubber asphalt are evaluated using Brookfield viscosity test and aging test. The result shows that（ 1） the significant sequence of various factors affecting rubber asphalt ＇ s orthogonal test is rubber powder dosage matrix asphalt type rubber powder mesh;（ 2） mixing time and mixing temperature have significant effect on the performance of rubber asphalt,which should be controlled reasonably in the process of preparation of rubber asphalt;（ 3） the best performance of rubber asphalt can be made by choosing asphalt No. 90 adding60 mesh,20% dosage rubber powder and mixing 60 minutes at 190 ℃. It is suggested that taking ductility at5 ℃ and viscosity at 180 ℃ primarily,and needle penetration and softening point secondary as the evaluation index of rubber asphalt＇ s performance.