SBS对高掺量胶粉改性沥青高温性能的影响

Effect of SBR on High-temperature Performance of High-volume Rubber Powder Modified Asphalt

通过三大指标试验、旋转粘度试验、高温PG分级试验和多应力重复蠕变回复试验(MSCR)对不同SBS掺量(0、1%、2%、3%、4%、5%)的高掺量胶粉改性沥青(内掺35%)的基本性能和高温性能进行研究,全面研究SBS掺量对高掺量胶粉改性沥青高温性能的影响,探究高温法制备高掺量胶粉改性沥青的可行性。研究结果表明:随着SBS掺量的提高,高掺量胶粉改性沥青的针入度不断减小,软化点、延度和运动粘度不断增大;高温PG分级试验和MSCR试验均表明,高掺量胶粉改性沥青高温性能差,复配SBS后,其高温性能提升明显,当SBS掺量为3%时,复合改性沥青的高温PG分级为76℃,弹性性能也十分优越;当SBS掺量较高时,继续增加SBS掺量对复合改性沥青高温性能的提升贡献很小,所以从性能和经济角度综合考虑,35%高掺量胶粉改性沥青的推荐掺量为3%、4%。

Through three major index tests,rotational viscosity test,high temperature PG classification test and multi-stress repeated creep recovery test(MSCR),the basic performance and high-temperature performance of high-volume rubber powder modified asphalt(mixed by 35%)with the different SBS contents(0,1%,2%,3%,4%and 5%)are studied.The effect of SBS content on the high-temperature performance of high-content rubber powder modified asphalt is comprehensively studied.And the feasibility of preparing the high content rubber powder modified asphalt by high temperature method is explored.The research results show that with the increase of the SBS content,the penetration of the modified asphalt with high content of rubber powder continues to decrease,and the softening point,ductility and kinematic viscosity continue to increase.Both the high temperature PG classification test and the MSCR test show that the modified asphalt with high content of rubber powder has poor high-temperature performance.After compounding SBS,its high-temperature performance is significantly improved.When the content of SBS is 3%,the high-temperature PG classification of composite modified asphalt is 76°C,and its elastic properties are also very superior.When the SBS content is high,the continuous increase of the SBS content will make little contribution to the improvement of the high temperature performance of the composite modified asphalt.Therefore,from the perspectives of performance and economy,the recommended content of 35%high-content rubber powder modified asphalt is 3%and 4%.