Study On The Damage Of Snow Melting Agent To Asphalt Pavement In Urban Road

The temperature is lower in winter,and the surface of the road is prone to snow and ice under snowfall conditions,reducing the speed of driving and increasing the incidence of traffic accidents.Nowdays,Scattering snow melting agent is the most common and effective method of removing snow.However,the large amount of snow melting agent is very harmful to the environment and the road surface.At present,the research on the damage of snow melting agent mainly focuses on the corrosion of concrete by snow melting agent,while the research on the road performance and service life of asphalt concrete is relatively rare.Therefore,it is necessary to analyze the damage of asphalt concrete snow melting agent.In this paper,the gradation design of AC-13 asphalt concrete is firstly carried out by Marshall test to obtain the best asphalt content.The snow melting agent melting test is carried out to determine the test concentration and pH of the snow melting agent.Then,through the indoor road performance test,the influence of the snow melting agent on the road performance was analyzed.Finally,the effects of snow melting agent on the splitting strength and void ratio of asphalt concrete were analyzed by salt freeze-thaw cycle test.The freeze-thaw test results were used in the salt-freeze-thaw damage evolution model,and the salt-thaw-thrust damage life prediction method was proposed.The main research is as follows:?1?The gradation design of AC-13 asphalt concrete by Marshall test to obtain the best asphalt content.And the snow melting agent test concentration and pH value were determined by the snow melting agent melting test.?2?Prepare test specimens based on the optimum asphalt content.The road performance of asphalt concrete etched by snow melting agent was studied by the salt marathon test,the salt immersion test and the low temperature trabecular test.A group of snow melting agents with good effect of melting ice and little influence on asphalt pavement performance are proposed.?3?Through the salt freeze-thaw cycle test,the effects of snow melting agent on the splitting strength and void ratio of asphalt concrete under freezing and thawing conditions were investigated.As the number of freeze-thaw cycles increases,the splitting strength of asphalt concrete decreases and the void ratio increases.When the concentration and the number of freeze-thaw cycles are fixed,the order of the splitting strength of asphalt concrete decreases slowly as NaCl>CaCl₂>NaAc.?4?According to the results of freeze-thaw test combined with Weibull model,the freeze-thaw damage evolution model of asphalt concrete eroded by snow melting agent was established,and the scale factor?,shape factor?and gradient factor?were obtained.?5?The weakening factor k of the snow melting agent to the asphalt mixture was established to evaluate the ability of the snow melting agent to resist the freeze-thaw resistance of the asphalt mixture,and the residual life of the asphalt concrete eroded by the snow melting agent was estimated.