Research On Structure Thickness Of Continuously Reinforced Concrete Composite Asphalt Pavement

Because of the serious early-damage,the actual pavement life of freeway is lower than expect life in our country usually, so it is needed urgently to improve the durability of road engineering, promoting better and faster development of our country transportation business. Continuously reinforced concrete composite asphalt pavement (CRC+AC) has the advantages of high strength of the whole structure, comfort of vehicle running, long life, low costs of maintenance, is the development direction of long life asphalt pavement in heavy traffic freeway.This paper is mainly focus on the structure characteristics and flaws of existing studies of CRC+AC composite pavement, finite element method is applied to researched the structure thickness of CRC+AC composite pavement.CRC+AC composite pavement finite element models based on crack pattern are established, the critical load position of CRC+AC composite pavement is found out under different crack spacing, the relationship of structure thickness and the maximum principal stress of CRC is analyzed under variable modulus, reinforcement rate, reinforcement position; The field of CRC+AC composite pavement temperature is simulated under the conditions of continuous temperature, the temperature stress and maximum temperature gradient of CRC are calculated, the relationship of the structure thickness of AC and CRC and the temperature stress and maximum temperature gradient is analyzed, the regression relationship of the maximum temperature gradient of CRC and the structure thickness of AC and CRC is established; Influences of structure thickness and overloading on the depth of rutting and the dynamic response of stress and deflection are analyzed, maximum shear stress of the bottom of AC layer is analyzed and calculated with the crack of CRC, and regression is used to get a relationship of rutting depth and the thickness of AC layer and a relationship of the maximum shear stress on the bottom of AC layer and the thickness of AC layer, respectively; Stresses state of asphalt concrete under traffic loads are analyzed, using fracture mechanics theory and finite element method, the reflective crack propagation mechanism of CRC+AC composite pavement is researched, the reflective crack propagation strength is calculated, and the influences of structure thickness and crack length on the I and II reflective crack propagation is researched and analyzed.The results can provide a theoretical basis for rational design of structure thickness of CRC+AC composite pavement.