论文部分内容阅读
冷再生乳化沥青混合料中存在水泥乳化沥青胶浆对回收沥青路面材料(RAP)粘附不均匀以及浸水易剥落等问题,直接影响了混合料的水稳定性等路用性能。国内外对水泥乳化沥青胶浆与RAP粘附程度多采用定性评价,缺乏便于操作且能够精确量化的测试方法。利用HCl溶液侵蚀水泥乳化沥青胶浆薄层模拟试验,运用数字图像技术对回收沥青路面材料(RAP)进行二维形状特征提取,提出了RAP表面积计算模型;同时设计了不同形状指数的RAP与水泥乳化沥青胶浆粘附性试验,并对粘附界面的胶浆用HCl溶液进行侵蚀试验,以20min内Ca2+和Mg2+的释放量表征RAP表面胶浆层的抗盐酸侵蚀性和粘附均匀性。研究结果表明:HCl对水泥乳化沥青胶浆有侵蚀特性,可腐蚀胶浆中水泥的水化产物相;集料形状指数对水泥乳化沥青胶浆平均膜厚度影响不大;RAP形状指数越大,离子释放量与粘附量的比也越大,胶浆粘附层抗盐酸侵蚀能力下降,粘附的均匀性和粘附等级变差;随着水泥与乳化沥青质量比C/EA的增加,离子的释放量先减小后增大,胶浆粘附性先增大后减小;当C/EA为30%时,离子释放量最小,粘附性最佳。
Cold-emulsified asphalt mixture has some problems, such as uneven adhesion of recycled asphalt pavement material (RAP) and easy peel-off of cement, which directly affects the road performance such as water stability of the mixture. At home and abroad for the cement emulsion asphalt mortar and RAP adhesion degree to use more qualitative evaluation, the lack of easy to operate and can be accurately quantified test methods. Using HCl solution to erode the thin layer simulation experiment of cement emulsified asphalt mortar, the digital image technology was used to extract the two-dimensional shape characteristics of recycled asphalt pavement material (RAP), and the RAP surface area calculation model was proposed. Meanwhile, RAP with different shape index and cement Emulsified asphalt mortar adhesion test, and the adhesion interface mortar with HCl solution erosion test, Ca2 + and Mg2 + release within 20min characterization of RAP surface mortar anti-hydrochloric acid corrosion resistance and adhesion uniformity. The results show that: HCl has the erosion characteristics of cement emulsified asphalt mortar, which can corrode the hydration product phase of cement; the shape index of aggregate has little effect on the average film thickness of cement emulsified asphalt mortar; the larger the RAP shape index, The greater the ratio of the amount of ions released and the amount of adhesion, the lower the erosion resistance of the adhesive layer against hydrochloric acid, the worse the uniformity of adhesion and the adhesion level. With the increase of mass ratio of cement to emulsified asphalt C / EA, The release amount of ions first decreases and then increases, and the adhesiveness of the glue first increases and then decreases. When the C / EA is 30%, the ion release amount is the smallest and the adhesiveness is the best.