Preparation And Properties Of Crumb Rubber Modified Asphalts Coating

The continued growth of car ownership led to a large number of waste tires.The increasing figure of waste tires has produced negative influences on the natural environment like environmental pollution,fire,unbalance of ecosystem.The waste tire made of rubber powder into the asphalt to be modified and then add a certain amount of other modifiers with fillers,producing the Crumb rubber modified asphalt which is able to work as the waterproof material.Turning waste into treasure,reducing the cost of waterproof materials,will have an important engineering application value.In this paper,by analyzing the conventional test results of asphalt,the influence of material factor and preparation technology on the performance of crumb rubber modified asphalt are determined.Rubber powder modified asphalt was prepared by two different polymers,SBS and APP,Taking the elastic recovery and softening point as the main indexes of high and low temperature,the influence of the type and amount of modifier on the properties of composite modification were studied.The thermal aging properties of rubber powder modified asphalt were evaluated by means of thermal oxidative aging test with mass loss and residual penetration ratio as indexes.Talc powder and fly ash were selected as fillers,and a kind of rubber powder composite modified asphalt coating material was prepared by blending.Meanwhile,taking water resistance,low temperature flexibility,maximum tensile force and elongation as the main indexes,the influence of kinds and amount of fillers on the properties of coating materials was studied.The influence of UV aging on the properties of the coating was studied by means of the UV softening test and the softening point increment and the decrease of the flexibility at low temperature.The results show that: The reasonable preparation process of crumb rubber modified asphalt is crumb rubber particle size of 80 mesh,dosage 20%,mixing temperature 200 degrees,shear time 50 min,shear rate 5000rpm;With the increase of modifier content,the penetration of crumb rubber composite modified asphalt decreased,softening point,elastic recovery and viscosity gradually increased;When the content of SBS was 5%,the elastic recovery increased by 57.5%,and when the content of APP was 15%,the softening point reached 102?;Compared with the matrix asphalt,the quality loss of crumb rubber modified asphalt TFOT decreased by 50%,and the residual penetration ratio increased by 40%;With the increase of filler content,the penetration,elastic recovery and elongation of crumb rubber composite modified asphalt coating gradually decreased,softening point,viscosity and maximum tensile force increased gradually,and the flexibility at low temperature decreased slightly,and the water permeability was good;The filler content is 40%,and the crumb rubber modified asphalt coating has the best comprehensive performance;Compared with talc powder,the composite modified asphalt coating powder with fly ash has better performance index,The Brinell viscosity of rubber powder /SBS composite modified asphalt coating increased by 20.4%,the maximum tensile strength increased by 10%,and the flexibility at low temperature was no crack at-21?;The softening point of rubber powder /APP composite modified asphalt coating can reach 119?;The coating with fly ash showed better anti ultraviolet aging performance.Under UV irradiation intensity of 800 mu w/cm2,the aging strength and softening point increment of 7 days decreased by 28.9%,and that of low temperature flexibility decreased by 25%;The technical specification requirements of rubber powder composite modified asphalt coating material for waterproof material are put forward.