Study On Damping Characteristics Of Cement Asphalt Emulsion Mortar

As the cement based composite viscoelastic material,cement asphalt emulsion mortar(CA mortar)has been widely used in high-speed railway track construction in recent years.However,with the increase of service life,cracks and damage defects appear gradually under the track of high speed railway,which seriously affect the safety of high-speed railway train and the maintenance of the later period.In view of the workability,mechanical performance,frost resistance performance and damping performance of CRTSII cement asphalt emulsion mortar,the anionic and the cationic two kinds of emulsifier were used to prepared cement asphalt emulsion mortar.11 groups of cement asphalt emulsion mortar with different asphalt emulsion contents were prepared.In order to study the effects of different asphalt emulsion types and different asphalt emulsion contents to the workability,mechanical performance and frost resistance performance of cement asphalt emulsion mortar,the tests were done according to standard.According to the research results of the performance of cement asphalt emulsion mortar,the interaction between cement and asphalt emulsion is studied and analyzed combined with XRD and SEM micro methods.On this basis,the coagulating and hardening process of cement asphalt emulsion mortar slurry is briefly described.In order to study the effect change law of different temperature ranges,different loading frequencies,different asphalt types and different asphalt emulsion contents to the damping performance of cement asphalt emulsion mortar,the tested were done by DMA-Q800 dynamic mechanical analyzer.The effects of different asphalt emulsion contents on the performance of cement asphalt emulsion mortar was analyzed and studied by grey correlation theory.The results show that the fluidity of cement asphalt emulsion mortar decreases with the increase of asphalt emulsion content,but has no significant effect on the extensibility.The loss factor is selected as the evaluation parameter to evaluate the damping performance of cement asphalt emulsion mortar.The loss factor of the cement asphalt emulsion mortar rises and then decreases with the increase of temperature.The higher the frequency is,the smaller the loss factor is.The loss factor and modulus of the mortar prepared by anionic asphalt emulsion of them were higher than those of cationic asphalt emulsion.The amount of asphalt emulsion has a direct effect on the damping performance of cement asphalt emulsion mortar.The higher the asphalt emulsion content is,the greater the loss factor is.The anionic cement asphalt emulsion mortar is superior to cationic cement asphalt emulsion mortar in its workability,mechanical performance,frost resistance performance and damping performance.The grey correlation analysis shows that when the content of asphalt emulsion is 40%(anionic emulsion)and 30%(cationic emulsion),the contribution of asphalt emulsion to the cement asphalt emulsion mortar is the most,and the performance of the cement asphalt emulsion mortar is in a good state.Therefore,the two mixture ratios are the best proportion to reflect the performance of cement asphalt emulsion mortar.