改性钢渣-沥青混合料的性能及机理

Properties and Mechanism of Modified Steel Slag-Asphalt Mixture

采用甲基硅酸钠溶液、二氧化硅胶体溶液、聚丙烯酸酯乳液对钢渣进行浸泡改性处理,通过性能测试、扫描电子显微镜(SEM)、声发射等测试方法研究了改性钢渣的物理、力学性能,改性钢渣-沥青混合料的性能,钢渣的改性机理和改性钢渣-沥青混合料的抗裂机理。结果表明,4.75~19 mm钢渣经1%~4%浓度溶剂改性后,物理性能得到明显改善;经3%浓度溶剂改性后的钢渣制备的改性钢渣-沥青混合料的体积稳定性较未改性钢渣-沥青混合料(RSAM)提高了27.92%~39.09%;改性钢渣表面包裹着不同状态的不溶于水的改性保护层,经二氧化硅改性后的钢渣(SMS)表面呈现出致密的层状结构且保持表面粗糙,改性效果最优;二氧化硅改性钢渣-沥青混合料(SMSAM)的裂纹宽度减小,主裂纹出现的时间较晚,SMS对SMSAM的断裂破坏起到了一定的减缓作用,提高了混合料的抗开裂性能。

The steel slag was soaked and modified using sodium methyl silicate solution,silica colloidal solution,and polyacrylate emulsion.The physical and mechanical properties of modified steel slag,the properties of modified steel slag-asphalt mixture,the modification mechanism of steel slag and the crack resistance of modified steel slag-asphalt mixture were investigated by property testing,scanning electron microscope(SEM),acoustic emission and other test methods.The physical properties of 4.75-19 mm steel slag were improved after modification by 1%-4%concentration of solvent.The volume stability of modified steel slag-asphalt mixes prepared from modified steel slag with 3%solvent concentration increased by 27.92%to 39.09%compared to unmodified steel slag-asphalt mixes(RSAM).Modified steel slag surface wrapped with different states of insoluble modified protective layer,the surface of the modified steel slag(SMS)showed a dense layered structure and kept the surface rough,and the modification effect was the best.The crack width of silica modified steel slag-asphalt mixture(SMSAM)was reduced and the main crack appeared later,SMS played a role in slowing down the fracture damage of SMSAM and improved the cracking resistance of the mixture.