چكيده به لاتين
Due to the importance of roads in creating connections between different areas, the issue of road maintenance is always a vital issue for road organizations. Preventive maintenance is a method used to manage and maintain pavement. The purpose of preventive maintenance is to repair early damage, reduce the speed of deterioration and delay of pavement deterioration, and reduce the need for corrective maintenance, and Surface Treatment is one of the most practical methods. In terms of materials used, the slurry seal is a mixture consisting of emulsion bitumen, crushed rock material, mineral filler, water, and additives needed to control the breaking time. To improve the performance of slurry seal mix the effect of using SBR / PS polymer blend as a modifier of emulsion bitumen and the addition of polypropylene fibers in slurry mixing design has been investigated. Accordingly, bitumen was modified with three different ratios of 70/30, 50/50, and 70/30 from SBR / PS. Based on the results obtained from bitumen tests, the best sample was selected and five different mixes containing polypropylene fibers at different dosages, namely 0, 0.05, 0.10, 0.15, and 0.20% by weight to the weight of total aggregate were tested. Analyses were performed by doing 30-min and 60-min wet cohesion tests, loaded wheel test, and wet abrasion test according to ASTM D6372. The results of bitumen tests showed that the bitumen in this study performed well after being modified with polymer blend so that by using polymer blend, the degree of penetration decreased. in equal proportions of the polymer blend, by increasing the percentage of polymer blend from 2% to 4% softening points for the ratios of 70/30, 50/50, and 70/30 of SBR / PS increased by 5.41, 0.3, and 1.32 percent,respectively, in the sample Used in 2% polymer blend, the higher SBR ratio, the lower the Jnr parameter, while in 4% samples, this trend was not observable, and based on the same experiments, the SBR70 / PS30_4% sample was selected the best sample to use in The slurry seal mixture. The results of design and performance tests of slurry seal mixtures showed that the modified mixtures with polypropylene fibers improve slurry performance. Among the mixtures, the slurry seal mixture containing 10.0% of fibers increased adhesion to bitumen for 30 and 60 minutes, reduced vertical and lateral displacement, and improved abrasion resistance and reduced bitumen. At the other end of the spectrum, the results showed that excessive incorporation of the polypropylene fibers into the slurry seal mix would inhibit optimal dispersion of the fibers across the mix, leading to accumulation of the fibers in the form of nodules and hence deteriorating the mix performance
