Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Indirect Tensile Strength Ratio

Assessment of the Effect of Nono-clay on Recycled Asphalt Mixtures Resistance to Moisture

Mays A. Jaafar; Hasan H. Joni; Hussein H. Karim

Engineering and Technology Journal, 2022, Volume 40, Issue 11, Pages 1441-1447
DOI: 10.30684/etj.2022.133022.1164

Introducing nanotechnology to the pavement industry witnessed a great interest due to the proven benefits of nanotechnology in various scientific fields. However, the reduction in the binder's characteristics might be disadvantageous to the durability of the recycled mixture, making it more susceptible to external factors such as moisture. Therefore, using nanotechnology is expected here to treat this issue. The goal of the current paper is to report on the influence of the nano-clay montmorillonite (MMT) powder (MMT k10) on the resistance to moisture in the hot recycled mixtures or the Reclaimed Asphalt Pavement mixtures (RAP mixtures). In this work, different proportions of rejuvenated RAP were employed. These proportions are 30, 40, and 50% as a percent of the overall weight of the mix. The percentages were mixed with a nano-modified neat binder with  (0, 1, 3, and 5)% nono-clay MMT as a proportion of the bitumen’s weight. Two types of mixtures are prepared and used in this paper: nano-modified RAP mixtures and unmodified RAP mixtures. On both types of mixtures, the compressive strength test, the index of retained strength (IRS), the indirect tensile strength tests (ITS), and the tensile strength ratio (TSR) were carried out to compare and evaluate the moisture resistance of rejuvenated RAP mixtures. The experimental test results indicated that using 5 percent nono-clay in regenerated RAP mixes provides better performance than not using it.  where it increased moisture damage resistance by5.53% for IRS value and 3.66% for TSR for 50 percent RAP mixes.

Effect of Adding Used-Foundry Sand on Hot Asphalt Mixtures Performance

Hasan Hamodi Joni; Hussein HamelZghair

Engineering and Technology Journal, 2016, Volume 34, Issue 6, Pages 1253-1264

Highway material researchers have been investigating the use ofbyproduct materials such as used-foundry sand as a fine aggregate and mineral filler in asphaltic concrete mixtures to replace the traditional asphalt mixes by new one contain this type of sand. This researchshow a study using of used-foundry sand as an alternative to filler and fine aggregate in hot asphalt mixture, aims to minimize the environmental effect caused by this waste materials. To evaluate mechanical properties, the mixtures were designedby Marshall method which contain the used- foundry sand and determine indirect tensile strength ratio and then compared with hot asphalt mixtures contained of two types of filler(ordinary cement and limestone dust).The results showing that the reuse of foundry sand in the mixtures of hot mix asphalt as a partial replacement of fine aggregate that retained on sieve No 200 and a total replacement of filler material is viable and can be used in asphalt mixtures production. The hot asphalt mixtures containing of used-foundry sand with cement filler type improved the moisture sensitivity performance as characterized in indirecttensile strength ratio. Furthermore, that theresults obtained from Marshall stability test indicate maximum Marshall stability obtained for mixtures with cementand used-foundry sand more than these stabilities for mixes with used-foundry sand and lime stone dustas a filler were (15.3, 12.5 and14.1) respectively .