Mechanical Characteristics Of Asphalt Pavement Potholes Repair Structure

A road network based on asphalt pavement has been formed with the rapid development of expressway in China.As one of the common diseases of asphalt pavement,potholes not only reduce the service life of roads and waste social resources,but also directly affect traffic safety.At present,the hot repair,cold repair and heat regeneration are used for the repair of asphalt pavement potholes,but the area of potholes is still easy to be damaged again,and repeated maintenance of the potholes not only increase the economic cost,but also the long-term closed traffic disturbs directly the social order,so it is particularly important to analyze the mechanical characteristic of the potholes repair structure and provide theoretical support for improving technology and the quality of potholes repair.Through to summarizes the reasons for potholes,repair mechanism and the reasons of secondary damage after maintenance of potholes,according to the stress distribution of potholes,the article determine the mechanical index to analysis of relate factors impact on the structure of potholes.The mechanical index include tensile stress of patch block and waterproof material,the shear stress of waterproof material and bonding layer.Based on the structure form of the potholes maintenance of asphalt pavement,this paper established the finite element model by the ANSYS to calculate the most unfavorable loading position in potholes repair.Three load cation forms are selected(represented by A,B,and C respectively)of the load center acting on the edge of the patch block,the load acting on the outer,and the inner edges of the wall joints.Determining the most unfavorable load positions to determine the most unfavorable load position for potholes repair through moving them.The results show that the most unfavorable loading position of tensile stress for patch block and waterproof material is C1-1(A2-2),the most unfavorable loading position of shear stress for waterproof material and bonding layer is B2-1and C1-5,respectively.Subsequently,the influences of the patch block modulus,waterproof material,original pavement material,size and thickness are calculated by using the finite element model under the most unfavorable load position,at the same time,the degree of influence of related factors on the repair structure of potholes are analyzed through orthogonal test.Then the mechanical characteristic also are analyzed of prefabricated maintenance of asphalt pavement potholes.The results show that the tensile stress of the patch block and the shear stress of the bonding layer increase gradually with the increase of the modulus of the patch material,but the tensile stress of waterproof material reduce;the tensile stress of the patch block and the shear stress of bonding layer reduce gradually with the increase of the modulus of the waterproof material,but the tensile stress and the shear stress of the filling material are varied in a contrary trend;when the modulus of patch block,waterproof material and original pavement material change,the most dangerous position became C1-2,the corner of the patch block;the stress of the potholes structure reduce if the patching thickness;the modulus of patch block,waterproof material and bonding layer have a significant influence on the stress of patch block and waterproof material,the stress of the potholes repair structure can weak with the increase of the thickness of the structure of the pothole repair.The shear stress of the leveling layer in the structure of prefabricated maintenance for asphalt pavement potholes shows different change for related factors.According to the results of the analysis of the relevant factors on the stress of the asphalt pavement repair structure,the paper put forward some more legitimate suggestions for repairing the potholes,and conduct field test for the prefabricated maintenance of asphalt pavement potholes.