Asphalt binder, which is a by-product of petroleum distillation, is vastly consumed in pavement construction. However, petroleum is highly rare as a nonrenewable source resulting in the short-term supply of petroleum asphalt. The improper elimination of waste oils and plastics presents numerous environmental problems. This paper investigates the possibility of using waste vegetable oil (WVO) in combination with waste plastics; Low density polyethylene (LDPE) and Polyvinyl chloride (PVC), as enhancing additives for (40/50) asphalt cement in order to mitigate the illegal disposal of these wastes and modify asphalt binder properties as well as reduce the consumption of bitumen thereby reducing the cost. Three percentages (1%, 2% and 3%) of waste vegetable oil were firstly added to the control asphalt to prepare WVO-modified bitumen. Three percentages (1%, 3% and 5%) of LDPE and PVC were then added separately to WVO-modified binder. Physical properties of the original and modified asphalts were studied using several laboratory tests. The results indicated that bitumen modified with waste vegetable oil has better thermal cracking resistance and lower rutting resistance and it is more suitable to be used in moderate and cold regions, while the addition of plastic wastes in combination with waste vegetable oil could reverse these effects. As a final result, utilizing suitable amounts of waste vegetable oils and waste plastics as asphalt cement additives can give new binders that are suitable for both hot and cold regions. Finally, it can be concluded that the recycling of waste oils and plastics in hot mix asphalt industry is workable and can be seen as a convenient and valid method for eliminating these wastes.

The temperature and stress caused by the load can be cited as two main parameters leading to breakage in asphalt pavement, especially rutting (permanent deformation). So, to reduce the problems of rutting of roads, several actions have been taken, including improving pavement quality and the structure design methods. The increase in the attention of respective engineers in the last few years to modify and improve the asphalt performance through providing different types of additives and replacing the raw materials of asphalt mixture with recycled materials to improve the environment and reduce the cost of modified pavement mixture. This study discussed the use of low-density waste polyethylene as an asphalt modifier in percentages of (2, 4, and 6) % by the weight of asphalt and their impact on the performance of asphalt mixtures at high temperatures. This study showed that using plastic waste (low-density polyethylene) as a bitumen modifier improved the performance of asphalt mixtures at different high temperatures. This was achieved by reducing the rut depth by (80.5) % and (82.3) % at temperatures of 50 C and 60 C, respectively, using low-density polyethylene waste at an optimum value of about 4% by weight of asphalt in addition to enhancing the Marshall stability by using this percentage of polymer.

Nowadays, in Iraq, especially Baghdad, many accidents are recorded daily, and the occurrence is different in terms of severity (fatal, injury, property damage only) with different seasons, days and even times, as a result of the anxiety and great concern that these accidents pose on the part of drivers of these highways. Therefore, this study has become necessary to find out the causes which have direct interference with the accident impact on these roads. On the other hand, many researchers in the field of traffic engineering in Iraq didn’t address the severity of accidents on highways. In addition, this study is the first to find out the main causes of accidents for the most important main and vital highways that are used on a daily basis by drivers on the Al- Rusafa side in Baghdad (Mohamed Al-Qasim Expressway, Army Canal expressway). Furthermore, the data utilized in this research consists of a sample size of (236) forms and it was collected from traffic officers for period 2006 to 2019. After analysis by using Logistic Regression Model, there are three variables closely linked to the severity of accidents on Mohamed Al-Qasim Expressway (cause of an accident like (wrong turn, loss of control, closing (safety distance), vehicle body type, speed). Also, and four variables on Army Canal Expressway (road condition, day, vehicle body type, speed) resulting from the Binary Logistic Regression model.

Fatigue and moisture damage have been recognized as the most prevalent problems on asphalt roads, necessitating large annual expenditures for road maintenance. Much industrial waste is added to bitumen paving to enhance its conventional quality while decreasing the negative impacts on the natural environment and increasing resistance to pavement distress. This research uses ground granulated blast furnace slag (GGBFS) to substitute conventional filler (Portland cement [PC]) in hot mix asphalt (HMA). To determine how the GGBFS affects the HMA's susceptibility to moisture and fatigue cracks, Marshall characteristics, tensile strength ratio (TSR), and index of retained strength (IRS) of the asphalt concrete were evaluated. HMA was prepared with different rates of GGBFS (0, 25, 50, 75, and 100%) instead of PC. The data support the usage of 50% GGBFS in asphalt pavements as a partial replacement of PC, which enhanced Marshal stability by 34.4%, reduced flow value by about 12.9%, and increased TSR and IRS by 11.1 and 14.54%, respectively. The fatigue resistance of the modified asphalt mix at the optimum rate was evaluated with the four-point bending beam test; the fatigue life (Nf) increased by 33.8% relative to the reference mixture. The results obtained from this research hold scientific value for researchers and method designers aiming to enhance the resistance of hot asphalt mixtures to moisture and cracking. Using waste materials as an alternative to PC contributes to cost reduction while mitigating the environmental damages associated with cement manufacturing. To summarize, this research highlights the significance of exploring sustainable options in the construction industry, emphasizing the importance of reducing costs, and minimizing environmental impacts.

The increased demand for asphalt and other materials involved in the construction of pavement led to an increase in the cost of these materials, which calls for searching for alternatives to virgin materials that can be used to produce asphalt mixtures. Reclaimed asphalt pavement (RAP) was employed in this study and regenerated using oxidized asphalt modified with waste engine oil (WEO). This method can achieve economic and environmental benefits. After improving the properties of oxidized asphalt using WEO, it was used with reclaimed asphalt mixtures (RAP). When the RAP was added at ratios of 20, 30, 40, and 50%, an improvement can be noticed in the mechanical performance of the asphalt mixtures renewed with oxidized asphalt and WEO and an increase in its resistance to stripping. When reclaimed asphalt pavement (RAP) is added to hot mix asphalt (HMA) at concentrations of 20, 30, 40, and 50%, respectively, the Marshall stability of HMA is improved by 10, 20, 28, and 9.5%, the flow is declined by 1% for all ratios of RAP except for 50% RAP where the flow decline by 3%, the unit weight is enhanced, the quantity of air voids in the mix is preserved within allowable ranges, and the resistance to stripping is increased by 62, 77, 85, and 76%, respectively. Research also shows that incorporating 40% RAP enhances the resistance to moisture by about 5.9%. The addition of 40% RAP reduced the Cantabro loss values by about 2 and 16% for both aging and non-aging samples, respectively. The rutting resistance increased by 50 and 47% for mixes with 40% RAP at 50 and 60°C, respectively. As a result, it became evident that mixtures containing RAP material could be effectively adapted to satisfy the relevant volumetric and performance requirements.

In this study, hybrid functional fillers were used to create an electrical network that is used to develop self-damage sensing ability within conventional cementitious mixtures. This electrical network was used to examine the self-sensing properties of cementitious composites under different loading scenarios such as compression, splitting tensile, and cyclic loading for three ages, those are 7, 14, and 28. With the help of a single type of functional filler or fiber, the self-sensing capabilities of the majority of previous works are demonstrated. This study incorporates two types of functional fillers for sustainability and low cost: micro-scale carbon fibers (CF) and waste iron (Ir) powder in the form of microparticles. The purpose of the current work is to fill up the subject’s gap using two different types of functional fillers as a hybrid form. Three hybrid proportions of a micro-scale CF (vol% of mixture) and waste iron powder (Ir) (wt% of cementitious materials) are utilized. These are (0.33, 15), (0.67, 10), and (1.00, 5), respectively. Unlike carbon-based materials, polyvinyl alcohol is used as a mechanical reinforcing fiber 2% by volume of the cementitious mixture. Additionally, a control combination without any fillers has been created. The electrical resistivity of the fabricated samples was monitored during various loading applications for every second to confirm their self-sensing capabilities. Regarding the fractional change in electrical resistivity, the self-sensing behavior was superior for mixes containing high dosages either of waste iron powder or CF in the same hybrid matrix. Quite the contrary to that, the piezoresistivity was modest in the middle hybrid ratio.