Mining Induced Failure Characteristics And Deformation Prediction Method Of High-grade Highway

High-grade highway is an important infrastructure for coal mining area and many mining areas are facing the problem of coal mining under high-grade highway.Accurately predicting and evaluating the influence of mining deformation of high-grade highway is an important prerequisite.In this paper,the New Zouji Highway in Nantun mining area is taken as the research object,the deformation and failure characteristics of the High-grade highway under the influence of mining,the relationship between surface and pavement deformation and the process of highway deformation and damage are studied by means of field measurement,theoretical analysis and simulation.The method of pavement deformation prediction in mining area is established and programmed.The main research results are as follows:(1)Surface movement and deformation are transmitted to the subgrade and pavement,causing the pavement subsidence,horizontal movement,tilt,horizontal deformation and others,which change the geometric structure of the highway.When the pavement movement and deformation exceed the limit value,the crack occur in the drawing area,the uplift is raised in the compression area,the curb is broken and the damage changes the continuity of the road surface,which increase the unevenness of the pavement and seriously threaten the safe operation of the road.The measured results show that when the pavement subsidence reaches 21 mm and the inclination deformation is 0.73mm/m,the crack was first generated.When the compression deformation reaches 1.8mm/m,the uplift was first generated.(2)For flexible pavement of New Zouji Highway,when pavement does not produce uplifts,the pavement and the corresponding surface movement and deformation basically the same.The subsidence of the pavement is lagging behind the corresponding surface subsidence,and the horizontal movement of the pavement is larger than that of the surface.Between the pavement and the surface there is no significant layer development.Therefore,the movement and deformation of the pavement at the corresponding position can be replaced by the predicted value of the surface.(3)In view of the low prediction accuracy of dynamic deformation of highway,combined with the High-grade highway under the coal mining need to carry out deformation monitoring the favorable condition,a high precision dynamic prediction model of surface subsidence is established.The dynamic prediction model needs to be integrated into the measured data.Aiming at the problem of poor adaptability of irregular face in rectangular model,which is commonly used in the prediction model,an prediction program based on triangulation method is developed.The results of case analysis show that the dynamic prediction model based on the measured data predicts pavement subsidence that the relative error of the maximum subsidence point is less than 6%.