Available online at www.CivileJournal.org Civil Engineering Journal (E-ISSN: 2476-3055; ISSN: 2676-6957) Vol. 7, No. 09, September, 2021 1529 Performance Evaluation of Fatigue and Fracture Resistance of WMA Containing High Percentages of RAP Saad Tayyab 1* , Arshad Hussain 1 , Fazal Haq 2 , Afaq Khattak 3 1 School of Civil and Environmental Engineering (SCEE), National University of Sciences and Technology (NUST) Islamabad, Pakistan. 2 National Institute of Transportation (NIT), Military College of Engineering NUST Risalpur, Pakistan. 3 Department of Civil Engineering, International Islamic University Islamabad (IIUI), Pakistan. Received 25 May 2021; Revised 27 July 2021; Accepted 09 August 2021; Published 01 September 2021 Abstract Sustainability and durability are the key requirements of pavement structure. Sustainability of asphalt pavement structure involves utilization of Warm Mix Asphalt (WMA) technologies with the addition of Reclaimed Asphalt Pavement (RAP), where durability of asphalt involves performance parameters like fatigue and fracture resistance properties etc. Utilizing the RAP content in asphalt mix increases the mixing and compaction temperature which may degrade the performance of asphalt. Hence, numerous studies have recommended different WMA technologies to decrease mixing and compaction temperature of asphalt mix containing RAP. The present research work evaluates the fatigue and fracture performance of WMA and Hot Mix Asphalt (HMA) with varying percentages of RAP and Sasobit. Different mixes of WMA and HMA were designed with varying percentages of RAP (0, 20, 40 and 60%) through Marshall Mix design. Sasobit (organic/wax-based additive) was used as WMA technology to prepare WMA at varying percentages (0, 2, 4 and 6%). The fatigue behavior of asphalt was evaluated using four-point bending test, where fracture resistance of asphalt was determined using Semi Circular Bending (SCB) test in the laboratory. Fatigue and fracture resistance of WMA were improved with the increase in percentages of Sasobit and RAP content, while the addition of RAP in HMA showed a decreasing trend of fatigue and fracture resistance due to the stiffer nature of RAP. Furthermore, WMA was identified as economical for construction besides other benefits like improved properties and environment friendly asphalt mix. Keywords: Warm Mix Asphalt (WMA); Hot Mix Asphalt (HMA); Fracture Resistance; Fatigue Cracking; Reclaimed Asphalt Pavement (RAP); Sasobit. 1. Introduction Production asphalt mixes with WMA technologies and RAP materials are emerging technologies and gaining popularity to deal with the concern related to energy consumption and global warming throughout the world. WMA technologies permit 10-30 o C lower mixing and compacting temperatures than conventional HMA. The conventional HMA are compacted at 145-150 o C and mixed at 150-155 o C [1]. The reduction in mixing and compacting temperature during mix production will in turn lead to less fuel costs in production and laying of asphalt mix. In addition to cost saving, less fuel consumption leads to lower greenhouse gases and fumes emission during mix preparation by asphalt plant and makes it more eco-friendly [2]. World Bank estimates the sustainability of WMA and emphasized that each * Corresponding author: saadtayyab@nit.nust.edu.pk http://dx.doi.org/10.28991/cej-2021-03091741 © 2021 by the authors. Licensee C.E.J, Tehran, Iran. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/).