1 1. INTRODUCTION Permanent deformation is the most common mode of failure in road pavement, especially in hot climate area like in Indonesia which the maximum pavement temperature of more than 50°C throughout the year. The temperature is major influence upon the permanent deformation mode of asphalt concrete, especially when the temperature rises above 40°C or higher because the asphalt concrete tends to flow out as viscoelastic materials do at high temperatures. There are several factors affecting the magnitude and the rate of permanent deformation (rutting) on the road pavement. The binder has an important role to play in the performance of bituminous materials, particularly in asphalt concrete where the mechanical properties of binder have a major influence upon the mechanical properties of the mixtures. The use polymer additive is one of the ways to improve the behaviour several properties such as temperature susceptibility, resistance to permanent deformation and fatigue live but the polymer is categorized in expensive material in developing country such as Indonesia. For that reason, it is needed to investigate the application of new materials but low cost such as waste plastic as a modifier to anticipate those problems. Development of waste plastic milk bottle as modifier in bitumen is the promising way on bituminous road construction industry in Indonesia as developing country. There are a variety of methods and devices that have been used to assess the permanent deformation resistance of bituminous mixtures. Permanent deformation assessment can classified into three groups i.e. fundamental tests; empirical mix design related test and simulation test. Wheel tracking as simulative method is commonly used to assess permanent deformation of mixture because the Repeated Load Axial Test as fundamental method can be categorized in expensive apparatus at developing country like Indonesia. In this research, fundamental and simulative methods used for assessing the resistance to permanent deformation were the Repeated Load Axial Test (RLAT) and wheel-tracking test. The objectives in this study are to investigate the effect of waste plastic (HDPE) added to bitumen on properties modified bitumen, investigate and correlation analysis the permanent deformation (rutting) characteristics of asphalt concrete from these methods. PERMANENT DEFORMATION EVALUATION OF MODIFIED WASTE PLASTIC- BITUMEN IN ASPHALT CONCRETE USING FUNDAMENTAL AND SIMULATIVE METHODS Imam ASCHURI, Lecturer, Civil Engineering Department, National Institute of Technology, Jl. PHH. Mustapa 23, Bandung, Indonesia E-mail : aschuri@itenas.ac.id David WOODWARD 1) , Alan R. WOODSIDE 2) 1) Lecturer, 2) Professor, University of Ulster, Transport & Road Assessment Centre, Jordanstown BT37 0QB, Northern Ireland, UK ABSTRACT: The paper discussed the fundamental and simulative method in assessing permanent deformation of modified waste plastic- bitumen in asphalt concrete. Waste plastic (HDPE) obtained from milk bottle plastic was used to modify 60/70 penetration grade bitumen and its effect on basic bitumen properties was tested over a range of test temperatures. The Marshall stability tests were carried out to determine the optimum bitumen content and optimum waste plastic content of asphalt concrete. The optimum waste plastic content in binder was found to be 1.5% by weight of binder. The permanent deformation evaluation of asphalt concrete with and without waste HDPE was evaluated in laboratory using fundamental method (Repeated Load Axial Test) and simulative method (Wheel Tracking Test) at a range of test temperatures. The analysis data indicated that both tests fundamental and simulative test had significant correlation with each other. Both test results was consistent that the performance of asphalt concrete prepared using waste plastic were more resistance on permanent deformation over a range temperature.. Keywords: Permanent Deformation, Asphalt Concrete, Waste Plastic, Fundamental Methods, and Simulative Methods