اسراء رشيد عداي الجبوري

At the present time, most researchers have tended to achieve the principle of sustainability in terms of cost reduction in addition to reducing and limiting environmental problems and preserving natural resources through the use of some modified materials and materials that achieve all of the above. Therefore, this research paper aims to study the effect of addition of both ordinary Portland cement and waste (natural marble powder) on the performance of cold mix asphalt (CMA) instead of limestone powder (LD) as a filler. Those CMA mixtures were improved through two stages: the first stage of development included the use of OPC as filler instead of the traditional mineral filler, and in three doses i.e., 2, 4, and 6 % of the total weight of the aggregate. While the second stage of development included the use of Natural Marble Dust (NMD) with 2% OPC with three percentages i.e., 2, 4, 6 % of the total aggregate weight to indicate, the optimum proportions to be compared with the OPC which was used alone and reference filler. All samples were subjected to indirect tensile strength test at a temperature of 25ͼC for four treatment periods i.e., 1, 3, 7, and 30 days. The samples were also tested to indicate ITS at a treatment period of 7 days with different temperatures i.e., 25, 40, and60 ͼC as well. A Marshall test was also performed to indicate the stability for the produced mixtures. The results showed that the use of 6% of OPC contributed to improving the mechanical properties of the mixture and increasing its strength compared to the percentages of 2 and 4% of using OPC as well as when using LD in all tests. In addition, the best results for the ITS test were achieved at the lowest temperature of 25ͼC. The use of NMD waste improved the strength of the mixture in all tests significantly and distinctly compared to the use (2, 4) % of OPC and as well as when used LD. Where the current study found the possibility of adopting using of (2% OPC plus 4% NMD) as optimal filler ratios used to improve the properties of CMA in order to achieve best mixture by means of mechanical properties and sustainability as well as economic.

Abstract. Despite there are many benefits that cold bitumen emulsion mixtures (CBEMs) have, it is trailing behind in the fields of use and research compared to Hot Mix Asphalt (HMA). It is less attractive to the researchers' attention due to its high content of air gaps and its poor resistance to its early life, meaning that it needs longer treatment periods, as each of that was the main motive for the current research paper, which aims to improve the mechanical properties of the cold asphalt mixture using Ordinary Portland Cement (OPC) and another Sulphate-Resistant in proportions (2,4, and 6)% by mass of aggregate for each of them as fillers in the mixtures. Where the results were compared with the mixtures in which traditional limestone powder was used. Indirect Tensile Strength was used to compare between the two mixes with different treatment periods i.e. 1,3,7, and 30 days at 25℃. This test was also used for a treatment period of 7 days at different temperatures 5,40, and 60℃. Also, Marshall test and long term ageing test were conducted in this study. The results for each of the above tests showed a great improvement of both types of cement i.e. OPC and SRC. The current study indicates the possibility of adopting both 2% OPC and 2% of SRC as optimal percentages used to improve the properties of CBEMs, it also showed that using 2% SRC imoroved the mixingproperties better compared to 2% OPC.