MOISTURE DAMAGE AND FATIGUE EVALUATION OF HOT MIX ASPHALT (HMA) CONTAINING RECLAIMED ASPHALT PAVEMENT (RAP) AND POLYTHENE BAGS (LDPE)

Abstract

Transportation infrastructure plays a key role in the everyday life of social beings. For its design, highway agencies focus on appropriate and cost-effective design technique so for this purpose Reclaimed Asphalt Pavement is being used for the last many years. Its utilization has now turned into a typical practice in various nations. The use of RAP not only conserve our natural resources but also to use the waste materials for a useful purpose, meeting economic and environmental friendly needs of a country. Same is the case for Polythene Bags which is used extensively all over the world for carrying shopping items. These bags are being burned or dumped on certain sites which create air and soil pollution producing dioxins which are quite injurious for human beings. These polythene bags can be used in HMA lessening the bitumen quantity. Pavements over time gets damaged by rutting, fatigue, moisture susceptibility render it unusable for vehicles. Therefore, it is needed to have such design which are cost effective and environmental friendly. The use of Reclaimed Asphalt Pavement (RAP) and polythene bags (LDPE) acts a distinct part in achieving national prosperity. This project is based on evaluating the performance of Hot Mix Asphalt (HMA) by using different contents of Reclaimed Asphalt Pavements (RAP) and Polythene bags (LDPE) as a replacement of bitumen. NHA gradation B, ARL grade 60/70, RAP from Islamabad Lahore M2 and LDPE from the dump yard of Islamabad were used in this study. Penetration, Ductility and Temperature testing were done on virgin bitumen with different percentages of LDPE i.e. 1%, 2%, 3%, 4%, 5% and 6%. The RAP contents used were 10%, 20%, 30% and 40% with 4% LDPE of Bitumen content. Performance testing was done after finding out the OBC, volumetric, stability and flow of RAP containing mixtures. Using those OBC and adding 4 % LDPE as replacement of bitumen, different samples were formed and tested for evaluation and compared with the performance testing results of mixtures containing RAP only. Performance testing’s included indirect tensile Fatigue Test (ITFT) and Moisture susceptibility using Universal Testing Machine (UTM). It was noted that 20% RAP with 4 % LDPE as a replacement of bitumen can be used which would give better properties than control mix of virgin materials. Cost estimation was also done which showed 21.8% reduction in cost.