No abstract

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.

No abstract

The purpose of this research is to assess the suitability of dune sands as construction materials, moreover, such a purpose is considered beneficial in assessing appropriate methods for soil stabilization or ground improvement and to assess the suitability of dune sands as subgrade layer for carrying roads and rail foundation. Dune sand samples were collected from a region in Baiji area in Salah-Aldeen governorate, North of Iraq. A grey-colored densified silica fume (SF) and lime (L) are used. Three percentages are used for lime (3%, 6% and 9%) and four percentages are used for silica fume (3%, 6%, 9% and 12%) and the optimum percentage of silica fume is mixed with the percentages of lime. Unsoaked CBR on compacted dune sands treated dune sands with L-SF by mixing and cured for a period of 1 day. The increasing in CBR ranged between 443 -707% at 2.54 mm penetration and 345 -410% at 5.08 mm penetration.El propósito de esta investigación es evaluar el uso de arena de dunas como materiales de construcción. Además, este objetivo permite determinar los métodos apropiados para la estabilización del suelo, el mejoramiento del terreno y la evaluación de pertinencia de la arena de dunas en capas subbase para carreteras y cimientos férreos. Se recolectaron muestras de arena de dunas en el área de Baiji, del comisionado Salah-Aldeen, al norte de Irak. Se utilizó vapor de óxido de silicio (SF, en inglés), grisáceo y densificado, y óxido de calcio (L). Se utilizaron tres porcentajes para el óxido de calcio (3 %, 6 % y 9 %), y cuatro para el óxido de silicio (3 %, 6 %, 9% y 12%) y el máximo porcentaje del óxido de silicio se mezcló con las proporciones de óxido de calcio. Se realizó en seco el Ensayo de Relación de Soporte de California (del inglés California Bearing Ratio, CBR) en arena de dunas compactada y tratada con la mezcla L-SF curada durante un día. El incremento en el ensayo CBR osciló entre 443-707 % en la penetración de 2.5 mm y 345-410 % en la penetración de 5.08 mm. ABSTRACT RESUMEN

The aim of this paper is to evaluate traffic performance of Al-Ameer signalized intersection in Samawa city, which fits with the prevailing conditions and geometric properties of the intersection. The technique of video recording has used for collection the traffic volume data for all approaches. These data are abstracted from video films. SYNCHRO 8 software was used to evaluate and analyze the intersection and choose the best suggestion. The evaluation process result showed that the intersection is operated with level of service (LOS F). By suggestion of several strategies which vary from signal optimization to geometric improvements. The best solution has been found by suggestion an overpass at the east-west direction, and the level of service has improved from (LOS F) to (LOS C), this result is considered an acceptable and economical solution for the existing problems at intersection.