Research On The Impact Of Different Viscosity Reducing Agents On The Road Performance Of Warm Mix Asphalt Mixture

Warm mix asphalt mixture is a new technology,which can lower the temperature of asphalt mixture in construction,save energy,reduce the amount of pollutants emissions in the construction process,and reduce the environmental pollution.At present,a series of experimental preliminary exploration has been carried out in the field of warm-mixed rubber asphalt at home and abroad,the types of viscosity reducers have been increasing.For example,Sasobit developed by Sasol-Wax Company in Germany,Aspha-Min developed by Eurovia Services Company in Germany,EC120 produced by Shenzhen Haichuan New Material Technology Co.Ltd.At the same time,the number of roads constructed by warm mixing technology is gradually increasing all over the world,and relevant technical specifications have been formulated in provinces and municipalities of China.However,there are many kinds of viscosity reducers with different action mechanisms and different effects.If they were used inappropriate,the performance of asphalt will be affected negatively.In this study,we select two kinds of viscosity reducer,EC120 and Sasobit,select 70# base asphalt and SBS modified asphalt as the basic raw materials.We adopt the method of controlling variables,adding two kinds of viscosity reducer into two kinds of base asphalt respectively,to explore the influence of viscosity reducer on asphalt.The change of asphalt performance is explored by parallel comparison.The study concluded that:Test the viscosity of asphalt and analyze the influence of different viscosity reducing agents on the viscosity performance of asphalt.At high temperature,the viscosity of asphalt can be reduced effectively because of adding viscosity reducer recommended.The optimal admixing quantity of EC120 in 70# base asphalt is 3.5%;the optimal admixing quantity of EC120 and Sasobit in SBS modified asphalt is 3%.Through the analysis of the conventional index of asphalt,it is found that the penetration of asphalt will be reduced by viscosity reducer at low temperature.At 25℃ and 30℃,when the content of Sasobit and EC120 is more than or equal to 3%,the penetration of asphalt will be reduced at least 20%.When the content of viscosity reducer is less than 3%,the penetration index of asphalt increases,indicating that viscosity reducer can reduce the temperature sensitivity of asphalt.When the content of viscosity reducer is 3%,the softening points of 70# base asphalt mixture and SBS modified asphalt mixture increase about 30℃ and 40℃ respectively.Viscosity reducer will reduce the ductility of asphalt.When the content of viscosity reducer in 70# base asphalt is more than 3%,and the content of viscosity reducer in SBS modified asphalt is more than 2%,the ductility of asphalt can not meet the requirements of basic specifications.Through the analysis of the road performance of warm mix asphalt mixture,it is found that the mixing and compaction temperature of 70# base asphalt and SBS modified asphalt are reduced by about 30℃ after adding proper viscosity reducer;after adding viscosity reducer,the compaction temperature of 70# base asphalt mixture and SBS modified asphalt mixture are 110℃ and 120℃ respectively;the viscosity reducer can improve the water stability and high temperature of asphalt mixture The stability and anti fatigue performance will have a negative impact on the low temperature performance of asphalt mixture,but the test results can still meet the requirements of the basic specifications.According to the test results in this paper,the road performance of warm mix asphalt mixture is better,the viscosity reducer EC120 can play a better viscosity reduction effect.This study not only provides a reference for the promotion of asphalt warm mixing technology,but also provides a basis for the selection of asphalt viscosity reducer.