A Study On Bonding Characteristics Of The Interface Between Cold Patch Asphalt Mixture And Old Pavement

In the using process of asphalt pavement,many kinds of diseases appear,which are affected by various factors such as the external environment and automobile load,and the pothole is a serious one.The pothole in the pavement not only reduces the smoothness of the road surface,shortens the service life of the road,but also seriously affects the safety of driving.There is a great potential safety hazard,so the pothole should be repaired in time.At present,cold patch asphalt mixture,the most commonly used pothole repair material,can repair the potholes quickly,promptly and conveniently.However,under the influence of various factors such as material composition,external environment and construction technology,the durability of the cold patch asphalt mixture is insufficient,and many secondary damages such as loose spalling,sag,falling off,and shifting occur shortly after the pothole repair.Therefore,this paper investigates the common failure modes and dominant failure modes of cold patch asphalt mixture in Harbin,and analyzes the force law of cold patch asphalt mixture and old pavement under moving load,and studies the cold patch asphalt mixture and old The influencing factors of the bonding characteristics of the pavement interface,the specific research contents and results are as follows:Through domestic and foreign literature research,it is clear that the common damage forms of cold patch asphalt mixture include loose exfoliation,interface failure,sag,displacement,shedding,oil flooding,cracks,etc.;according to the traffic volume of the road,the use condition and the repair after the pothole In the situation,four sections of Harbin were selected to investigate the damage form of cold patch asphalt mixture.It was found that the cold patch asphalt mixture in Harbin area will be loosely peeled off,interface damage,dent,displacement,and cracks.,where interface destruction is the dominant form of destruction.The ABAQUS software was used to establish the three-dimensional finite element model of the pothole.The force law of the interface between the cold patch asphalt mixture and the old pavement under the action of rectangular moving uniform load was studied.The horizontal interface and the longitudinal interface at different depths and horizontal directions were analyzed.According to the force law,the influence of load position on the interface force is clarified.The location of the dangerous point on the interface and the most vulnerable moment of the dangerous point are discussed.The influence of the elastic modulus of the cold patch asphalt mixture on the interface stress condition is clarified.The oblique shear test was used as the evaluation method,and the influence factors of temperature,humidity,binder type,binder spreading amount and interface roughness were analyzed.The influence of different factors on the interface bonding characteristics was analyzed.The humidity increases,the viscosity of the binder increases,and the interfacial bond strength gradually decreases;there is an optimum value for the amount of binder spread and the roughness of the interface.On this basis,through gray correlation analysis,the degree of influence of various factors is clarified,and the dominant factors affecting the interface bonding characteristics are the binder type and interface roughness,which should be paid attention to in practical engineering.