Domestic And Foreign Natural Asphalt Road Performance Of A Comparative Study

Based on the current research and development of natural asphalt in road engineering both in China and abroad, this paper systematically analyzes and examines the changes on the properties of base petroleum asphalt when adding four types of typical natural asphalts (including rock asphalt of Xinjiang , Sichuan and Utntahite as well as lake asphalt of TLA). It also studies the road performance when these natural asphalts are used as new kind of modifiers for petroleum asphalts.All four types of natural asphalts prove to be able to improve dramatically many qualities of the basis asphalt when added at different quantities. Improvements are observed in temperature sensitivity, high-temperature durability, resistance to aging, adhesion property, especially in high-temperature stability which are even more pronounced when the quantity of natural asphalt added is increased. However, low-temperature performance is affected by such additions. Experiments show that each type of natural asphalt has its own optimal proportion to the base asphalt to improve performance.According to the facts that performances of basis asphalt are improved by natural asphalts, properties of asphalt mixture are conducted. Experiment results show that all four types of modified asphalt mixtures have better performances on low-temperature stability, water-resistance, and especially high-temperature stability. This stability provides the new measure for vehicle track resistance under high temperature environment. Through comprehensive performance index comparisons and also considering cost effectiveness and ease of utilization in practical projects, natural asphalt from Sichuan has better overall performance result than the other three natural asphalts.It is proved that road petroleum asphalt mixed with some natural asphalt can form a uniform and steady mixture system because natural asphalts and road petroleum asphalts have the same components. Through component analysis of the asphalt materials, it can be find that natural asphalt contains more Asphaltenes and Resin which are the key elements that improve the composition and property of the road petroleum asphalt. It is the changes that mixtures with natural asphalts present better road performances.