Study On Rheological Properties Of OMMT/SBS Modified Asphalt

With the rapid development of China’s transportation infrastructure construction, the drastical growth of traffic volume, heavy-load, vehicle overloading, and canalized traffic, making the performance of asphalt pavement to face a severe test. In order to improve the quality of asphalt pavement, prolong the service life of the pavement and improve the investment benefit of the highway, SBS and nano montmorillonite modified asphalt pavement has attracted more and more attention by virtue of its excellent technical performance and simple construction technology, Therefore, the rheological properties and anti-aging properties of 90# matrix asphalt, SBS modified asphalt and OMMT/SBS modified asphalt are investigated.The rheological properties of the matrix asphalt; the SBS modified asphalt with content of 1%,3% and 5% respectively; OMMT/SBS modified asphalt containing 0.5% OMMT 1%,3%,5% SBS and 3%SBS, and 1%,2% OMMT respectively Using DSR test at medium and high temperature And using BBR on its rheological properties at low temperature evaluated. Through the analysis of the rheological property parameters of medium and high temperature, the improvement of the rheological properties of SBS modified asphalt is mainly concentrated in the temperature of 46℃～64℃, but in the high temperature stage, the influence of temperature on the rheological properties is dominant. In the SBS modified asphalt mixed with 0.5% of the OMMT, it is better to improve the rheological properties of 3%SBS modified asphalt in the middle and high temperature. In the 3%SBS modified asphalt mixed with 2% of the OMMT, it is good to improve the rheological properties of medium and high temperature. According to the test results of low temperature creep stiffness modulus S and creep strain rate m, the effect of SBS addition on the rheological property of asphalt at low temperature was significant. Through the analysis of S and m, the optimum SBS content of SBS modified asphalt was 5%. In addition, it has the poor effect of the SBS modified asphalt mixed with 0.5% of the OMMT in its low temperature rheological properties. However, the addition of 2%OMMT to the 3%SBS modified asphalt has a significant improvement in the low temperature rheological properties.For the same test materials, firstly using the asphalt rotary thin film oven and PAV pressure aging vessel respectively to simulate the short-term and long-term aging of asphalt, then using the DSR test and BBR test to evaluate the rheological properties of the medium, high and low temperature. After RTFOT and PAV aging, based on the analysis of the rheological properties of the medium, high and low temperature found that the OMMT content has a significant influence on the rheological properties of SBS modified asphalt in the middle, high and low temperature. With the increase of OMMT content, the effect of OMMT on the rheological properties of SBS modified asphalt was increased. In this study, mixed with 3%SBS and 2%OMMT has the most effect on the aging resistance of matrix asphalt.