基于表面能的Sasobit~影响WMA劈裂强度机理研究

Mechanism of WMA Splitting Strength of Sasobit~ Based on Surface Free Energy

为解决掺入Sasobit温拌剂后温拌沥青混合料(WMA)劈裂强度降低的问题,首先从材料表面能角度,采用躺滴法测定了Sasobit温拌剂掺量(质量分数,下同)分别为0%,2%,3%,4%的沥青表面自由能,分析了该表面自由能及相关参数的影响;其次对应成型不同Sasobit温拌剂掺量下的沥青混合料马歇尔试件,并测定其劈裂强度、冻融劈裂强度;最后分析不同温拌剂掺量下的沥青混合料劈裂强度与沥青表面自由能之间的关系.结果表明:沥青混合料劈裂强度与沥青极性分量呈负相关,而沥青混合料劈裂强度与沥青色散分量呈正相关;Sasobit温拌剂的掺加使沥青的色散分量减小,极性分量增大;掺有Sasobit温拌剂的沥青混合料劈裂强度降低.

As previous work reported that splitting strength of warm mix asphalt with Sasobit is lower. Surface free energy of asphalt with different Sasobit warm mix agent content （0 , 2%, 3%, 4%, by mass） was measured by the sessile drop method, and influence of Sasobit warm mix asphalt surface free energy and related parameters was analyzed. Corresponding to asphalt mixture Marshall test specimen in different Sasobit~ warm mix agent contents, splitting strength and freeze-thaw splitting strength were measured. Finally, relationship between asphalt surface free energy and splitting strength of asphalt mix- ture in different Sasobit warm mix agent contents was analyzed. The results show that polar component of asphalt and splitting strength is negatively correlated, but dispersion component is positively correlated; and Sasobit makes dispersion component of asphalt reduce, but polar component increase, so splitting strength of mixtures with Sasobit reduces legitimately.