增强型硫磺胶结料机理及混合料结构力学分析

Mechanism of enhanced sulfur binder and structural mechanical analysis of its mixture

为了提升Thiopave改性沥青混合料的水稳定性和低温性能,先加入双戊烯(dipentene,DIP)和硫磺,在高温条件下搅拌均匀。再加入丙烯酸异辛酯(ethylhexyl acrylate,EHA),继续高温搅拌。加热温度控制在140℃左右,将高速剪切搅拌机的转速缓慢提升至1500 r/min,持续反应4 h之后,冷却至室温,对Thiopave进行预处理,并对其改性机理、混合料路用性能和力学性能进行全面分析。研究结果表明:添加DIP和EHA后,硫磺分子链变长,硫磺胶结料的表面能和极性分量增加;与Thiopave改性沥青混合料相比,增强型硫磺改性沥青混合料的高温性能略有降低,而水稳定性和低温性能显著提高;与未改性沥青混合料路面相比,增强型硫磺改性沥青混合料路面的面层竖向总变形和变形贡献率均大幅下降。掺入1.0%DIP和0.5%EHA为最佳组合,能够明显改善增强型硫磺改性沥青混合料的路用性能和力学性能。

In order to improve the moisture resistance and low temperature performance of Thiopave modified asphalt mixture,dipentene(DIP)and sulfur were added and stirred evenly at high temperature,followed by adding ethylhexyl acrylate(EHA)and stirred well at high temperature around 140℃.The speed of mixer was slowly increased to 1500 r/min,and after reacting for 4 h,the Thiopave particles were cooled to room temperature for pretreatment.In the meantime,the modification mechanism and mixture road performance with its mechanical properties were investigated comprehensively.The results showed that the sulfur molecular chain became longer after the addition of DIP and EHA,the surface energy and polar fraction of the binder were increased.Compared with the Thiopave modified asphalt mixture,the high temperature performance of enhanced sulfur modified asphalt mixture was slightly reduced,while the moisture resistance and low temperature crack resistance were significantly improved.As compared to the unmodified asphalt mixture pavement,the total vertical deformation and deformation contribution rate caused by the surface course of the reinforced sulfur modified asphalt mixture pavement decreased significantly.It was revealed that 1%DIP and 0.5%EHA are recommended as the optimum dosage to apparently improve the road performance and mechanical properties of the enhanced sulfur modified asphalt mixture.