Experimental Study On The Properties Of Modified Normal Temperature Bio-asphalt And Mixture

With the aggravation of environmental problems and the shortage of petroleum resources,the traditional hot mix asphalt mixture can not meet the requirements of resource saving and environment-friendly.In this paper,the plant asphalt and unsaturated fatty acid from the castor oil foot are used as raw materials,which are mixed with the petroleum asphalt to make the normal temperature bio-asphalt.SBS is used to modify it,and then calcium hydroxide powder is used to solidify it to make the modified normal temperature bio-asphalt.The main contents are as follows:(1)Taking petroleum asphalt,plant asphalt,unsaturated fatty acid and SBS as raw materials and rotating Brinell viscosity as evaluation index,single factor test and orthogonal test were carried out to determine the final content of each component of modified normal temperature bio-asphalt.The final content is petroleum asphalt:plant asphalt:unsaturated fatty acid:SBS=100:30:20:4.The average storage stability of the modified normal temperature bio-asphalt is more than 99%.Taking the conventional performance of asphalt as the evaluation index,it is determined that the optimal content of curing agent is 6%.(2)DSR and BBR tests were used to test the rheology of modified normal temperature bio-asphalt and matrix asphalt.The PG grade of modified normal temperature bio-asphalt was pg82-28.FTIR and SEM were used to test the microcosmic properties of the modified normal temperature bio-asphalt.Before curing,the components of the modified normal temperature bio asphalt were physically dissolved and SBS was evenly dispersed.After adding the curing agent,the neutralization reaction between calcium hydroxide and the carboxyl group in the fatty acid occurred,and there were not many endothermic peaks in DSC test.(3)The mix proportion of the modified normal temperature bio-asphalt is designed with AC-13 as the target gradation,and the final optimal oil stone ratio is 6.7%.The construction workability,cohesion,mechanical properties,water stability,high temperature stability,low temperature crack resistance and sliding resistance of the modified normal temperature bio-asphalt mixture are tested.(4)According to the physical and chemical characteristics of plant asphalt and fatty acid,a special production process was designed for modified normal temperature bio-asphalt and its mixture.