Study On The Performance Of Resistance Water Damage Hard Asphalt And Asphalt Mixture

Asphalt Pavement is one of the main forms of Highway pavement structure in China, Used Asphalt and Asphalt Mixture are viscoelastic materials, as the temperature increases, their viscosity and hardness decrease, shear properties of material weak,In the early period according to our traffic conditions the pavement Bituminous material grade is high, In recent years the trend of global warming is enhancing and the rapid development Transportation and serious overload, leading to severe ruts, water damage and other problems of early disease in most parts of our country, especially in the southern areas of high temperature and rainfall the phenomenon is particularly serious.Using the hard asphalt is one of the ways to solve these problems. Hard asphalt is a low grade of asphalt, including a variety of craft production of petroleum asphalt and natural asphalt, such asphalt which has low needle, high softening point and large viscosity, has good high temperature stability. Foreign considerable research and practice have shown that: Hard asphalt can be used to improve the pavement rutting resistance, extend the service life and thinning the thickness of road pavement. In the manufacture of the bitumen mix some active ingredients to add its performance against water damage ,which will be a good solution to the asohalt pavement early disease problems .But the hard asphalt is a new type of asphalt for asphalt road of China, the research of its good high-temperature rutting resistance and other pavement performance is particularly urgent.In our country the use of hard asphalt is seldom, and the petroleum source of every country and the technique of productionis different, so that the production of the petroleum performance is not identical, in addition to the different climate and traffic conditions, so in our country it is necessary to study on hard asphalt.In this paper, we use laboratory material tests and mechanics analysis to study the performance of 30 # hard asphalt which was added active ingredients to provide against water damage. In Material field, use laboratory tests to study the high temperature performance, water stability properties and other pavement performance of 30 # asphalt and its mixture. In addition to routine testing, we also use the special adhesion apparatus and dynamic water pressure washing equipment of Our School Road Research Institute to evaluate the asphalt water stability. Finally, comprehensive Analysis and evaluate with the China's regulatory requirements and the European CEN technical indicators and the United States SHRP pavement performance specifications. Used hard asphalt as the surface of the commonly used semi-rigid asphalt pavement structure and then with BISAR procedures for structural mechanics analysis. Provide a more complete theoretical basis for the use of 30 # hard asphalt in the asphalt pavement and lay the foundation for the study and application of hard asphalt in our country.The results show that, hard asphalt has a low penetration, high softening point and viscosity, hard asphalt mixture has a good high temperature rutting resistance and water stability and other pavement performance. If asphalt pavement grass-roots level and below layer use hard asphalt, it can improve the overall strength, avoid forming cracks and increase road's fatigue life; if Asphalt pavement surface structure, especially the middle layer and upper layer where the shear stress is high use high modulus hard asphalt mixture,it will be very effective to improve the resistance of high temperature rutting and water damage of asphalt pavement.