Study On Freeze-thaw-scouring Performance And Snow-melting Performance Of Phase Change Material Asphalt Mixture

Phase change material asphalt pavement has a self-regulating function,delays the impact of high(low)temperature changes on the pavement,actively melts ice and snow,and has good timeliness to provide a good implementation environment for highway management departments to maintain and handle ice and snow disasters;The variable-material asphalt pavement also helps to reduce the traffic accident rate of special road sections in winter(long and large longitudinal slopes in mountainous areas,tunnel entrances,bridge pavements,high-speed gates),but nowadays,the freeze-thaw-scouring performance of the phase-change material asphalt mixture,The evaluation method of ice melting performance and the quantitative evaluation index need to be further studied.Therefore,the paper uses a more accurate evaluation method to improve the road performance of the phase change material asphalt mixture by testing the phase change material asphalt mixture’s freeze-thaw resistance and scouring performance and ice melting performance,and clarifies the phase change material asphalt mixture’s performance The scope of snow melting.First of all,carry out research on the design of the phase change material asphalt mixture mix ratio.Through the road performance test,the test results show that: the phase change material has little effect on the optimal asphalt dosage of the asphalt mixture,and has little effect on the water stability and low temperature crack resistance.It must be improved,but it will have an adverse effect on the dynamic stability.The excessive incorporation of DTC should be strictly controlled.Secondly,through the freeze-thaw-scouring test,the porosity and splitting strength of the phase-change material asphalt mixture are analyzed,and the technical requirements of the phase-change material asphalt mixture’s freeze-thaw-erosion resistance are put forward.The test results show that the incorporation of phase change materials can delay the decrease of the void ratio of the asphalt mixture,and the void ratio loss rate under 4 freeze-thaw-scouring cycles is more appropriate to reflect that the phase-change material asphalt pavement is fully damaged by freeze-thaw-scouring.;The recommended void rate loss rate standard recommended value is ≤25%.Finally,through the ice melting and snow melting performance tests,the evaluation methods and technical requirements for the ice melting performance of the phase change material asphalt mixture were put forward,and the snow melting application scope of the phase change material asphalt mixture was clarified.The test results show that the phase change material asphalt mixture can handle 47% to 93% of the thin ice on the road surface;the aver-age snow melting rate is proposed to reflect the melting ice capacity of the phase change material asphalt mixture,and the average melting rate of the phase change material asphalt mixture is recommended.The ice rate should be ≥0.181g/min;the phase change material asphalt mixture can better complete the snow melting task under light snowfall,and to a certain extent delay the time that the road is covered by snow under medium snow and heavy snowfall.Asphalt pavement not mixed with DTC has better timeliness;the recommended range of DTC is 0.4%～0.5%.The construction technology of the phase change material asphalt mixture pavement was studied,and the quality control points were determined;the physical engineering fully verified the temperature adjustment effect and the ability of melting ice and snow;The cost of phase change material asphalt pavement increases by 12% to 20% of investment per kilometer.The use of phase change material is more economical and environmentally friendly and has high social benefits.