Research On Road Performance Of SMA Mixture With Rice Straw Fiber In Seasonal Frost Region

Heilongjiang’s seasonal freezing area has special climate conditions.Rain and heat are at the same time,the freezing period is long,and the temperature difference between winter and summer can reach 80℃.This puts forward higher requirements for the asphalt pavement to have good high temperature stability,low temperature crack resistance,snow and ice resistance.At present,due to the advantages of high tensile strength,durability,and light weight,straw fiber materials are gradually used in asphalt mixtures.Heilongjiang Province,as a large rice production province,produces a large amount of waste rice straw every year,which can be made into rice straw fiber as a fiber stabilizer and added to the asphalt mixture to fully utilize the fiber itself,improve the performance of the pavement,and prolong the service life of the asphalt pavement.The study explored the use of rice straw fibers to improve the road performance of SMA,so as to be suitable for the climatic conditions in the seasonal freezing area of Heilongjiang Province,while reducing the environmental pollution of waste straws.Through Marshall test,rutting test,low temperature bending test,water immersion Marshall test,freeze-thaw splitting test,studied the effect of different fiber content on rice straw fiber Stone Matrix Asphalt’s road performance,and determined the optimal fiber content and asphalt content of rice straw fiber SMA.Using the structural depth test and the anti-skid performance test,the anti-skid performance of two types of rice straw fiber asphalt mixtures,SMA-13 and SMA-16,under seasonal freezing climate conditions is analyzed.The research results show that the incorporation of rice straw fiber improves the road performance of SMA-16 asphalt mixture.The mixture with 0.2%～0.3%rice straw fiber content has the best high temperature performance,The mixture with 0.3%～0.4%rice straw fiber content has the strongest resistance to water damage,and the mixture with 0.3%rice straw fiber content has the best low-temperature resistance to cracking.Under seasonal freezing climate conditions,SMA-16 rice straw fiber asphalt mixture has better anti-skid performance than SMA-13 mixture.It is recommended to use rice straw fiber SMA-16 asphalt mixture with a straw fiber content of 0.3%and an asphalt content of 5.93%.Its technical indicators meet the requirements of the technical specifications for the construction of highway asphalt pavements.It will provide theoretical basis and technical support for the application of straw fiber in asphalt pavement in seasonal frozen Areas,and realize energy saving,emission reduction and environmental protection.