Research On The Effect Of Residual Water On The Performance Of Cold Mixed Emulsified Asphalt Mixture

Compared with the traditional Hot Mixed Asphalt and Warm Mix Asphalt,Cold Mixed Asphalt are used as a new type of pavement material,it has the advantages of low energy consumption rate and low pollution emissions,etc.However,the research team found that the self-developed new Cold Mixed Asphalt(hereinafter referred to as CMA),because the mixing process of CMA requires additional water and there is water in the emulsified asphalt,it will leave some water after curing.Therefore,in this paper,the residual water content is used to characterize the content of residual water in the cold mix and to study the effect of residual water on the performance of the cold mix.The main contents include the effect of residual water on the high temperature performance,low temperature crack resistance,water stability,dynamic and static modulus,fatigue performance,aging resistance and water damage resistance of multiple freeze-thaw cycles of CMA.This paper analyzes the decay law of the residual moisture content of CMA with the curing time,and evaluates the high temperature performance,low temperature crack resistance and water stability performance of CMA at different residual moisture content.The results show that the above road performance of CMA increases with the decrease of residual moisture content.By controlling the curing conditions,this paper selected 12%,10%,8%,6%,4% and 2% of CMA specimens for the subsequent test.Firstly,the dynamic and static modulus of CMA at different residual moisture contents were measured.The results showed that the dynamic and static modulus values of CMA increased as the residual moisture content decreased.At the same temperature and loading frequency,when the residual moisture content is 12%,10% and 8%,the dynamic and static modulus values of CMA are less than the test value of the hot mix,when the residual moisture content is 6%,4% and 2%,the dynamic and static modulus values of CMA are greater than the test value of HMA.Secondly,after the combination of four single strains at 200??,400??,600?? and 800?? and two strain,tested the fatigue life of CMA under different residual water content.The results show that the fatigue life of CMA under the combination of single strain and two strain increases greatly with the decrease of residual moisture content.When the single strain of the CMA is greater,the decrease of residual water will obviously improve its fatigue performance.Under the effect of two strain combination,compared with the loading method from low strain to high strain,from high strain to low strain The reduction of residual water under the loading method will greatly improve the fatigue performance of CMA.Thirdly,multiple freeze-thaw cycles were used to analyze the effect of residual water on the water damage resistance of CMA.The results showed that the water damage resistance of cold mixes increased with the decrease of the residual moisture content.The degree of influence of the water resistance of the mixing material is greater than that of HMA.Finally,the effects of residual water on the anti-aging properties of CMA were analyzed by ultraviolet aging and temperature aging tests.In terms of UV aging,when the residual moisture content is 12%,10% and 8%,the strength,high temperature performance and water stability of CMA are affected by it more than HMA,and when the residual moisture content is 6%,4% and 2%,the above-mentioned performance of CMA is affected less than that of HMA,and the low temperature performance of CMA under the measured residual moisture content is greater than that of HMA;in terms of temperature aging,when the residual moisture content is 12%,10% and 8%,the strength and low temperature performance of CMA are affected by it more than HMA,and when the residual moisture content is 6%,4% and 2%,The above-mentioned properties of CMA are affected less than HMA,and the water stability performance of CMA under the measured residual moisture content is greater than that of HMA,and the degree of high temperature performance is less than that of HMA.