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Porous asphalt (PA) is widely used in a growing number of countries where porous asphalt is applied for a variety of purposes, e.g. for the effective drainage of rainwater, traffic safety (high slip resistance), the control of noise pollution and lower temperatures surrounding the city. However, it has many other disadvantages, such as poor resistance to rutting, poor resistance to fatigue, and PA is susceptible to raveling (wastage of aggregates from the pavement surface), due to effects of climatic and traffic loading. In general, this type of mixtures is not as good as traditional mixtures. This research aims to study and improve the properties of porous mixtures using SBS. In this paper, laboratory tests were carried out to the materials involved in the composition of this mixture: binder, aggregate, and additive. SBS is used in the proportion of (2.0, 3.0, and 4.0) % of the weight of the binder. It was found that this additive leads to reduce the permeability and air void, but not as large as that without polymer modifier by (1.7 %, 3%, and 3.5%), while in the case of abrasion loss (aged and unaged) decrease by (4.1, 6.67 and 10.92) (4.7, 6.3and 2.6)% respectively. The drain down value is decreased by (16.5%, 38.25%, and 43.51%) respectively, from original asphalt cement.

In Iraq, the severity of rutting has increased in asphalt pavements possibly due to the increase in truck axle loads, tyre pressure, and high pavement temperature in summer. As of late, Superpave has been accounted as an enhanced system for performance based design, analysis of asphalt pavement performance prediction for asphalt concrete mixes. In this research the development of permanent deformation in asphalt concrete under repeated loadings was investigated, Wheel-Tracking apparatus has been used in a factorial testing program during which 44 slab samples were tested to simulate actual pavement. The objectives of the present research include; investigating the main factors affecting rutting in asphalt concrete mixture, quantifying the effect of SBS polymer and steel reinforcement on asphalt concrete mixtures in addition to studying the effect of variables on the asphalt concrete mixes against moisture sensitivity. It has been determined that that increasing of compaction temperature from 110 to 150°C will decrease the permanent deformation by 20.5 and 15.6 percent for coarse and fine gradation control asphalt mixtures, respectively. While the permanent deformation decreases by 21.3 percent when the compaction temperature is increased from 110 to 150°C for coarse gradation SBS modified asphalt mixtures.

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The increase in heavy traffic load due to increasing number of vehicles and trucks with the effects of other exterior factors such air temperatures and moisture have caused distresses on pavement. In this study, the influence of laboratory aging on the mechanical properties of Polyethylene-modified concrete mixtures was studied utilizing different experiments. Polyethylene Terephthalate (PET) waste plastic bottles was used at different percentage i.e. 1%, 2%, 3%, and 5% by weight of bitumen. The design bitumen content was obtained for dense mixture according to superpave system. Marshall Stability, Flow, indirect tensile strength, and tensile strength ratio at two aging levels are conducted to evaluate the performance change of asphalt mixtures. Mixtures were conditioned at shortterm aging temperature of 135°C for different time periods (2, 6 and 8 hrs). Long-term aging was completed after compaction of test specimens to the desired air void level of 4 ± 0.5% using Superpave gyratory compactor at three different temperatures (75, 85 and 95) °C and four aging periods (0, 2, 5, and 10 days. The results showed that adding PET polymer to paving blend has good significance; it improved stability, flow, HMA density in addition to moisture resistance because of great elastic ability provided by PET particles, it can be found that 4 and 5% of PET content gave the best results as compared with the control mixture.

Transportation is an essential element for the development of countries economically, socially, and culturally. AL-Nasiriyah is one of the highly congested urban centers within Dhi-Qar province. Network in the city center suffers congestion, particularly during peak hours simply because of the existence of vitality centers (educational, commercial and government). The network is used to assess the flow of the current traffic network patterns through several programs such as the (TransCad, GPS, GIS) so collecting different types of data, such as (Traffic volumes and free flow speed) using a device (MSSS), field surveys is done for the work of large-scale map road network.The results of the evaluation showed that most of the roads in the city have a level of service type (B), as the network showed service-level type (F) at which the vehicle relative to the road capacity (v/c) is greater than one in the city center, such as (Habboubi Street, Nasir bridge, Sumer Street, etc.) as illustrated in analysis map. On the basis of that proposed to add new roads to change path of external - external trips and also add new bridges to get rid of the congestion that appeared in the city center.

This research investigates the behavior of Stone Matrix Asphalt mixtures (SMA) modified with styrene-butadiene-styrene (SBS) polymer at four percentages (1, 2, 3 and 4%) by weight of asphalt cement. The moisture susceptibility and rutting were taken into consideration in this study. To achieve the objective of this research the superpave system is conducted to design the asphalt mixtures. The physical properties of aggregate, bitumen and other mix materials were assessed and evaluated with the laboratory tests. The mixtures were prepared using penetration Graded (40-50) bitumen and a chemical named Polypropylene Fibers was used as a stabilizing additive. Fibers have been used in SMA mixtures for two main reasons: To increase the toughness and fracture resistance of hot mix asphalt (HMA) and to act as a stabilizer to prevent drain down of the asphalt binder. The laboratory tests include indirect tensile strength test, Marshall stability and retained Marshall Stability test (RMS). For rutting test the Roller wheel compactor is used for preparing the asphaltic samples and Wheel tracking device is used to evaluate the rutting of asphaltic slabs. The results showed that the SBS polymer asphalt mixture gave better moisture sensitivity and better fracture resistance according to the study.It is noted that indirect tensile strength ratio (TSR) increases by 93.1 % and the rut depth decreases by 32.5 % when adding 3% SBS polymer to SMA.