The Experimental Research Of High Viscosity Asphalt And Asphalt Mixture Of Drainage Pavement

Storm flood disaster and water contamination in the city are the key problems holding back the ecological development of cities in our country.In order to solve this problem,recent years we have come up with the policy of promoting the development of sponge city.Sponge city is based on the theories of best manage measures,low influence development and environmentalfriendly infrastructures,through the way of “Seepage,stagnation,storage,purify,use and discharge”,in order to achieve the purpose of “flexibility” while the city facing the environmental change and rain.Drainage asphalt pavement is a key technique of the construction Sponge city.Comparing with conventional dense graded asphalt pavements,drainage asphalt pavement has advantages of preventing water accumulation on surface,lowering the vehicle slip rate,reducing water mist and reducing the road noise.Due to the drainage functional needs,more coarse aggregate will be added into drainage asphalt mixture,and fine aggregate should be less or avoided in order to forge the formation of skeleton type interlocking structure and reach the goal of large porosity(air voids higher than 18%),resulting in larger internal frictional resistance and less cohesion of this kind of mixture structure.In order to gain greater strength and external resistance,bonding properties of cementing material is particularly important.Normal modified asphalt hardly meets the requirement;as a result,using high viscosity asphalt has become an inevitable choice.Common high viscosity modifier(such as TPS modifier)that used in China is mainly produced in Japan,which having high selling price,from the economic considerations it is not suitable for marketing.In recent years,domestic manufacturers have tried to produce high viscosity modifier,yet its practical application was limited due to the performance and workability.In this paper,a self-developed high viscosity asphalt modifier was added into matrix asphalt to produce suitable viscosity asphalt for drainage asphalt mixture,the performance of the high viscosity asphalt was evaluated from the macro-and micro-level.Then,the mathematic relation between grading and porosity was analyzed,and the water-film model of road surface in rain was built.Three kind of drainage asphalt mixture(OGFC-13)with different air voids was designed,and their road performance test and mechanical performance test were carried out.The influence of asphalt and air voids on the performance of drainage asphalt mixture was also analyzed.The purpose of this paper is to develop and marketing high viscosity asphalt with economical application,and promote the application and popularization of drainage asphalt pavement.It has great meaning for building Sponge City,improving the quality of the pavement,as for providing safer,more comfortable and more environmentally friendly road to the community.