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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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