In petrochemical industry, the production of polyvinyl chloride (PVC) is accompanied by formation of heavy end wastes which consist of a mixture of di and multichloro compounds as kind of materials which are generated in ethylene dichloride (EDC) purification. A high quantity of chloro compounds found in the heavy end waste allows it to be polymerized with alkaline polysulfides to form polysulfide polymers. Thus, according to this, the environmentally hazardous heavy ends waste can now be converted into useful polysulfide polymers without any environmental problem. There are some methods for synthesizing a polysulfide polymer (PSP) from this waste. PSP with a rubbery property can be used for modification of bitumen. In this research the effects of polysulfide polymer (PSP) and the polysulfide polymer prepared by heavy end waste (wPSP) on bitumen and ASPHALT have been studied. Samples of 1, 3, 5% of PSP and wPSP as modifiers in bitumen have been prepared and their physical and mechanical properties are compared. Using this new modifier causes a fall in softening point (PSP=39.5%, wPSP=27.6%) and increase in penetration point (PSP=17.8%, wPSP=15.5%) and in ASPHALT mixture it causes decreases in rutting but has a small effect on Marshall strength of ASPHALT samples (PSP=4%, wPSP=11.6%).

Roads are considered as the infrastructural and strategic capital of each country. A main part of the budget is allocated to the repair and maintenance of the roads. Any damage to the ASPHALT PAVEMENT will cause disturbance in the performance of the vehicles, which result in reduced driving safety and reduced riding levels. The damages to the ASPHALT PAVEMENT are due to various factors. In general, due to traffic jams, these damages emerge as small cracks in the PAVEMENT system, among which fatigue and cracks resulting from are the main causes of failure in the ASPHALT PAVEMENT. In fact, as a result of repeated loading, these small cracks are expanded in the form of fatigue cracking and eventually cause the rupture of the structure of the ASPHALT PAVEMENT. A major part of the annual budget is allocated to the repair and maintenance of the roads and eradicates the damages caused by the cracks. One of the factors that can be effective in increasing the fatigue life of the ASPHALT PAVEMENT is the self-healing potential of bitumen and ASPHALT. Self-healing means the ability to retrieve mechanical properties such as rigidity and resistance, as well as the return of displacement resulting from the opening of the cracks during the rest period and the high temperature period. In this research, the self-healing phenomenon and the factors affecting it are investigated, and the indices for measuring this ASPHALTic phenomenon are introduced and the results of the most recent studies are presented.

Now days, reclaimed ASPHALT PAVEMENTs are used in the production of ASPHALT mixtures. The use of this material has too many economic and environmental benefits. Beside, warm mix additives are materials that they reduce production temperature of ASPHALT mixtures and improve their workability in the constructed PAVEMENTs. There is always a question that “, what are the effects of reclaimed ASPHALT PAVEMENT and warm additive on the mix design parameters of ASPHALT mixtures? ”,In this research, the simultaneous effects of reclaimed ASPHALT PAVEMENT and a warm additive named Sasobit on the technical properties of ASPHALT mixtures were evaluated. For this purpose, an experimental plan was designed based on the response surface method for reclaimed ASPHALT PAVEMENT (from 0 to 50%), ASPHALT binder content (from 4 to 6%) and Sasobit content (from 0 to 3%). Then, the volumetric and strength properties of these mixtures were determined and compared with the Iranian PAVEMENT code criteria. Obtained laboratory results showed that an optimum point for fabrication of ASPHALT mixtures containing reclaimed ASPHALT PAVEMENT is a mixture with 4. 6% ASPHALT binder, 12% reclaimed ASPHALT PAVEMENT and 3% Sasobit additive. Also, increasing the amount of the Sasobit showed that it increases the value of the Marshal strength, ASPHALT unit weight of mixtures and it reduces its air voids.

Automatic PAVEMENT crack detection is essential for assessing road maintenance and ensuring safe driving. Traditional crack detection has problems such as low efficiency and lack of complete detection. This study aims to solving the problems of traditional crack detection methods and using deep learning models. We proposed a method based on object detection algorithms for PAVEMENT crack detection and discussed the latest YOLOv5 series models for PAVEMENT crack detection while explaining the theoretical concepts. Finally, a crack detection model and effective PAVEMENT management is presented. The proposed model can determine the type, position and geometric characteristics of cracks accurately and at a higher speed in comparison with other methods. For this purpose, the images that had been taken from the ASPHALT of Mashhad roads were used to train and evaluate the model. Images were labeled for both linear crack and surface crack. Proposed model is developed using five YOLOv5 series algorithms and transfer learning and were evaluated for accuracy and speed of prediction. The models’ accuracy is between 77 to 98% and the prediction speed is between 17.4 to 105 milliseconds, which indicates the optimal performance of the models. The v5s model with 92.8% accuracy and a speed of 23.9 ms is selected as the final model for real prediction of cracks in one of the main thoroughfares of Mashhad. Based on the dimensions and the type of predicted crack and the use of the proposed decision tree, the maintenance approach for each part was determined.

Half warm mix ASPHALT (H-WMA) is one of the alternatives to conventional ASPHALT due to its special production conditions.  Half warm mix ASPHALT (H-WMA) manufactured with high proportions of reclaimed ASPHALT PAVEMENT (RAP). Half warm mix ASPHALT (H-WMA) are produced and compacted at the temperature range of 60-100 ° C, which requires less temperature for production process of hot mix ASPHALT (HMA) for example cold mix ASPHALT (CMA) manufactured at a temperature lower than 60 ° C; (ii) half warm mix ASPHALT (H-WMA) manufactured at less than 100 ° C, normally at 60-100 ° C; (iii) warm mix ASPHALT (WMA) manufactured at temperatures of 100-140 ° C. The aim of this study is to investigate the effects of high percentages of reclaimed ASPHALT PAVEMENT (RAP) on the volumetric and mechanical properties of Half warm mix ASPHALT (H-WMA) mixtures. In this research, bitumen emulsion (CSS-1) and conventional bitumen 60/70 were used. The siliceous aggregates were obtained from a mine near Tehran and reclaimed ASPHALT PAVEMENT (RAP) were obtained from an ASPHALT plant and its granulation before and after extraction was done according to report number 234.  Generally speaking, in H-WMA, aggregates are heated to temperatures of 100-110 ° C and then mixed with emulsion, which has previously been heated to 60-80 ° C and RAP are heated to 90-100 ° C. To determine the most suitable mixing time in the tests, the coating was visually analyzed after mixing times of 1 and 2 min and the mixing temperature was 95-85 ° C. Thus, a laboratory analysis was carried out in which the behavior of half warm mix ASPHALT (H-WMA) manufactured with 100%, 70% and 0% reclaimed ASPHALT PAVEMENT (RAP) was compared with that of a control mix, Hot mix ASPHALT (HMA). Optimum bitumen content for hot ASPHALT mixture (HMA) and optimum bitumen emulsion content for half warm mix ASPHALT (H-WMA) were calculated. Then indirect tensile tests (IDT) (at 25° C), moisture damage (TSR) and Semi-Circular Bending (SCB) Tests (at 25° C and -20° C) were performed on half warm mix ASPHALT (H-WMA) and hot mix ASPHALT (HWA). indirect tensile tests (IDT) yielded acceptable results, the IDT resistance increased with increasing the reclaimed ASPHALT PAVEMENT (RAP) content. Following this, the moisture damage (TSR) of half warm mix ASPHALT (H-WMA) improves by increasing the reclaimed ASPHALT PAVEMENT (RAP) content, which can be due to the complete covering of the surface of the aggregates with aged bitumen and the high adhesion force between the aged bitumen and the aggregates and the lack of moisture penetration into the aggregates. emulsified bitumen exhibited proper volumetric (e.g., air voids and density) and mechanical behavior in terms of moisture damage and IDT. On the other hand, the results of SCB tests at medium and low temperatures showed that by increasing the RAP content the samples become brittle, which means that resistance to crack propagation reduced, and it may be the reason for fracture energy reduction. These findings encourage greater confidence in promoting the use of these sustainable ASPHALT mixes for their use in road PAVEMENTs or urban streets.

Adhesion of bitumen to Aggregates is the basis of the strength of the ASPHALT PAVEMENTs. The term "stripping" is used for hot mix ASPHALT (HMA) mixtures to show the separation of ASPHALT binder film from aggregate surfaces, due primarily to the action of moisture and/or vapor. If this phenomenon is eliminated for any reason, stripping will be occurred. This problem not only is as a distinct distress but also can cause other ASPHALT distresses which are finally resulted in the overthrow of road. Mainly because this distress either results from or is dominated by moisture, it is usually called“moisture damage” or “moisture susceptibility”.The main goal in this research is to study stripping in ASPHALT mixtures. The key factors which must be considered in this research are aggregates and selecting the suitable approach for controlling and assessment of this distress in laboratory conditions. the most recent approach introduced is the rehabilitation and modification of ASPHALT mixtures against stripping, whether ASPHALT concrete or surface treatment. Thus, in this study on "Zanjan-Qazvin" freeway where this distress have usually been observed, the aggregates for constructing the ASPHALT was selected from sections of the aggregate the stripping intensity of which is higher than the others. First, the sensitivity of stripping was specified by XRF & XRD analysis. There is a requisite to do a realistic laboratory test method to predict moisture susceptibility of HMA mixtures. It was observed in the case histories that the ASPHALT PAVEMENTs were saturated with water (55-80% saturated as specified in ASTM D4867 or AASHTO T283). Thereafter, in order to calculate the tensile strength ratio, it is required to consider unsaturated specimens some of which remained with no conditions. A laboratory test procedure that simulates such conditions will be more realistic. The cylindrical ASPHALT concrete specimens are constructed by marshal method. Thus, their durability is evaluated according to AASHTO-T283. In this method, those stabilities are measured by indirect tensile test; the amount of their stripping was previously estimated by boiling test. Results showed that according to literature boiling test method is not reliable enough to be accurate. On the other hand, the result of laboratory test of AASHTO-T283 is quantitative and much more technical. Also, using hydrated lime 3% for this material can be useful to reduce the adverse effect of stripping, and it can be used as a suitable anti-stripping. Based on the probabilistic analysis, all the specimens result either in Indirect Tensile Test, or in the TSR results. This showed the improvement of the strength. Also, the rate of increasing is close to that of the parabolic curve.WTAT test was carried out over the surface treatment specimens constructed using these aggregates. Hydrated lime was utilized as the most important anti-stripping additive for prevention and rehabilitation of this distress in all of the experiments.

Drainage conditions of base and sub-base layers are one of the key factors that affect serviceability of ASPHALT PAVEMENT of the roads. The non-destructive testing method of ground penetrating radar (GPR) has been considered as an applicable method in this respect. In this paper, the relationship between obtained data from recorded images by GPR machine and moisture content of ASPHALT PAVEMENT system was investigated. Eighteen cylindrical samples with 80 cm diameter and height were constructed from ASPHALT, base, sub-base, compacted medium and natural medium in three different moisture percentages, and then were compacted. Then, a GPR machine, with 250 MHz antenna, was conducted over samples for profiling survey and the obtained radar images were analyzed statistically using Labview software. Comparison of the statisticall parameters obtained from the images showed that distribution of kurtosis is similar to a normal distribution and has logical and interpretable variation-trend with moisture percentage. Therefore, by using a linear curve, fitted between kurtosis and moisture content, an equation was extracted which could help to estimate nearly accurate the moisture content of PAVEMENT layers, based on the output of GPR test.

A variety of factors such as amount of load, velocity, wheel impact, time (loading rate), rest periods, temperature, and stress state, loading modes, aging and moisture can affect the ASPHALT behavior against deformation and efficiency. One of the most important factors is the effect of velocity on the tensile strain of the ASPHALT sub-layer, which leads to the most common type of failure (fatigue). In this study, using Abaqus, Ansys and 3D move soft wares, the desired and then a comparison between these three soft wares has been made. Dynamic modeling is conducted relying on the elastic behavior of layers. The study also includes the impact of loading speed on tensile strain of ASPHALT sub-layer. Results have indicated that Abaqus software compared with Ansys operates faster and more comprehensive for PAVEMENT analysis. In addition, 3D move compared with Abaqus and Ansys operates more rapidly in various model of the visco, but Abaqus has a more varied and stronger dynamic analysis. The comparisons between different velocities showed that high velocities include less fatigue failure. In general, the impact of velocity on the tensile strain in the ASPHALT sub-layer is more remarkable at low velocities. At low velocities, changes occur due to approaching to the static mode.

The use of Reclaimed ASPHALT PAVEMENT (RAP) helps us save our natural resources and money. Of the different types of ASPHALT PAVEMENTs that can be built, HMA PAVEMENTs are considered the best in the terms of strength and durability. But the production temperature limits the amount of RAP used in the new mixture because this production`s high temperature requirement causes the deterioration of the aged binder of RAP and increases greemhouse gas emission. In the recent years there has been much focus on Warm Mix ASPHALT (WMA) technology, because the aim of this approach is to reduce the production temperature by using additives which increase the workability of the binder at a lower temperature. The use of WMA additives helps us reduce the temperature while preserving the desired workability, thus enables HMA to contain higher percentages of RAP. The purpose of this experimental study was to evaluate the effect of production temperature reduction by using WMA additives on the performance properties of ASPHALT mixture containing 100% RAP. To reach this goal, five mixes were prepared and tested: a control mix (100% RAP-mixing temperature 150° C), three mixes with Sasobit, Rheofalt and without additives (mixing temperature of 130° C), and one virgin mix with extracted aggregate (mixing temperature of 160° C). The performance properties of the mixtures were evaluated based on indirect tensile strength, resilient module, four point beam fatigue test, and dynamic creep test etc. The results showed that the mixtures with WMA additives had better performance according to their moisture susceptibility and rutting potential, but the control mix had better performance in fatigue and low temperature cracking.