大掺量胶粉改性沥青胶砂高低温性能研究

High and Low Temperature Performance of High-Content Rubber Powder Modified Asphalt Mortar

针对沥青胶砂性能问题,基于胶浆理论,利用高温锥人度试验和低温小梁弯曲试验对3种不同改性沥青(20%胶改性沥青,30%胶改性沥青以及SBS改性沥青)胶砂试件进行了试验研究。研究结果表明:随着温度的升高,沥青胶砂试件的抗剪强度降低,50℃时30%胶粉改性沥青胶砂的抗剪强度和-10℃时最大弯拉应变分别为SBS改性沥青胶砂的1.4和1.8倍,表明30%胶粉改性沥青胶砂比SBS改性沥青胶砂具有更良好的高低温性能;50℃时胶粉改性沥青胶砂的抗剪强度和-10℃时最大弯拉应变分别为20%胶改沥青胶砂的1.5和2.2倍,随着胶粉掺量的增加,可以有效改善沥青胶砂的高低温性能。

In view of the performance of asphalt mortar,based on the theory of mortar,three different modified asphalts(20% rubber modified asphalt,30% high-content rubber powder modified asphalt and SBS modified asphalt) mortar specimens were tested by high temperature cone penetration test and low temperature beam bending test.The research results show that the shear strength of the asphalt mortar specimens decreases with the increase of temperature.The shear strength at 50℃ and the maximum bending strain at-10℃ of high-content rubber powder modified asphalt mortar are 1.4 and 1.8 times more than those of SBS modified asphalt mortar respectively,which indicates the high-content rubber powder modified asphalt mortar has better high and low temperature than SBS modified asphalt mortar does.The shear strength at 50℃ and the maximum bending strain at-10℃ of highcontent rubber powder modified asphalt mortar are 1.5 and 2.2 times more than those of 20% rubber modified asphalt mortar respectively.With the increase of rubber powder content,the high and low temperature properties of asphalt mortar can be effectively improved.