为了评价废旧胶粉对不同基质沥青在流变性能方面的改性效果,在3种不同来源的基质沥青(克炼、埃索和SK)中添加不同掺量的废旧轮胎胶粉制备得到橡胶沥青,通过动态剪切流变试验和布氏黏度试验分析了基质沥青对橡胶沥青性能的影响,采用复数模量指数评价了不同基质沥青制备得到的橡胶沥青的感温性,并采用凝胶色谱试验分析了橡胶沥青中大分子(LMS)的变化.发现添加相同胶粉的克拉玛依沥青制备得到的橡胶沥青黏度最大、车辙因子最高、感温性最小、LMS值增长较为显著;埃索沥青制备得到的橡胶沥青黏度最小,车辙因子最低、感温性较大、LMS较其它橡胶沥青都小.随着胶粉掺量的增加,橡胶沥青的黏度和车辙因子增大,但是不同基质沥青制备得到的橡胶沥青的增幅不尽相同.结果表明:基质沥青组分对橡胶沥青的流变性影响显著,沥青质少、芳香分高的基质沥青对胶粉的分解作用越好,其制备得到的橡胶沥青的性能越好.
In order to study the effects of different virgin asphalt on rheological properties of crumb rubber modified asphalt, the crumb rubber modified asphalt was produced by three virgin asphalts (Karamay,Esso,SK) with different content of crumb rubber. The effects of different virgin asphalts on rheological properties of crumb rubber modified asphalt were analyzed by using dynamic shear rheometer(DSR) and Brookfield viscosity experiments. The temperature sensitivity of rubber asphalt binders were evaluated by the complex modulus index (GTS). And the asphalt rubber macromolecules (LMS) changes were discussed by high gel-chromatographic (GPC). It is pointed out that the crumb rubber modified asphalt constituted with Karamay has best rheological properties,i, e. the highest viscosity and rutting parameter, the lowest temperature sensitivity and increased values of LMS. However,the rheological properties of crumb rubber modified asphalt constituted with Esso are worst. The viscosity and rutting? parameter of crumb rubber modified asphalt will increase when the rubber content increase. But the increase value is different due to different virgin asphalt. The results show that the theological properties of crumb rubber modified asphalt are influenced significantly by the composition of virgin asphalt. The less asphaltenes and higher aromatics of virgin asphalt are, the better its decomposition is. It is helpful to produce the rubber asphalt binder with better rheological properties.