Study On Modification Mechanism Of Natural Asphalt To Base Asphalt

Natural asphalt is a kind of excellent modifier to improve road asphalt. It can effectively improve the road performance of the asphalt materials. This paper examines the modified mechanism for natural asphalt to perfect its modified technique.Based on the component analysis on the PanJin base asphalt and the asphalt modified by four typically natural asphalt (including rock asphalt of Xinjiang ,Sichuan and Utntahite as well as lake asphalt of TLA) we can see that after modified by natural asphalt the content of Asphaltene and the proportion between Asphaltene and Resin increases and the content of Resin decreases meanwhile the plus of Asphaltene and Resin increases. The result of DSC test indicates clearly of the relationship between the aggregation state for asphalt along with the heat absorption in the situation change for asphalt and the performance of asphalt. After modified by natural asphalt the temperature for asphalt to intenerate increases, the heat absorption decreases and the width in the figure for the maximum of heat absorption narrowed. The result of GPC test indicates that after modifying average molecular weight and number-average molecular weight are all increase in different extent. So after modified by natural asphalt, the temperature sensitivity of the asphalt improved wholly especially the high-temperature stability and the low-temperature performance is also improved in some extent.After modified by the four kinds of nature asphalt described above, through different time span of the TFOT test and component analysis the longer the ageing time the index of the colloid of PanJin base asphalt decrease but the trend is slow. So it indicates that nature asphalt can improve base asphalt's anti-ageing performance to some extent. Meantime, the infrared spectrum test indicates that nature asphalt can slow the increase rate of the carbonyl and sulfoxides index, postpone the time for the two kinds of component to reach the maximum value. It can reflect the nature asphalt's anti-ageing performance in microcosmic.Nature asphalt can improve the petroleum asphalt's adhesion property in a large extent especially to the granite. The ranges for them are all above 47%. The infrared spectrum test indicates that on the one hand natural asphalt contains polarity functional group of amides and it can bring strong adhesion power. One the other side, natural asphalt contains a great number of functional group for Naphthalene and the functional group can improve the petroleum asphalt's originating Cefdinir to make the molecule arrange method and the reticulate structure of the petroleum asphalt changed to improve asphalt's cohesion and anti-tension strength and improve the petroleum asphalt's adhesion property.