Research on Dynamic Response and Impact Resistance of Airport Pavement Made of Gradient Carbon Fiber Reinforced Composites

Aiming at the engineering problems of easy cracking and insufficient impact resistance of traditional airport concrete pavement under complex dynamic loads, this paper studies the application of functionally graded carbon fiber reinforced polymer ( FG-CFRP) in airport pavement. Based on the modified Halpin-Tsai model and the first-order shear deformation theory, the dynamic finite element control equation is established. Based on the COMSOL Multiphysics platform, the modal characteristics and transient impact response analysis are carried out, and the dynamic response of the aircraft under moving wheel load is simulated. The static bending test of FG- CFRP plate samples made in the laboratory was carried out, and the numerical model was calibrated. The relative error of test-simulation was controlled within 5 %, which verified the accuracy of predicting static response. The carbon fiber volume fraction gradient curve was parametrically studied to reveal the sensitivity of the gradient to impact and stress reduction. The key engineering factors such as long-term environmental durability and life cycle cost of FG-CFRP pavement are discussed, and targeted improvement and optimization strategies are proposed. The results show that the fundamental frequency of the gradient plate is about 1.93 % lower than that of the homogeneous plate, and the vibration mode characteristics are highly consistent. The peak displacement of transient impact is reduced by 9.4 %. Under the action of moving wheel load, the peak Von Mises stress decreased from 5.32 MPa to 2.15 MPa, with a decrease of 60 %. The gradient design realizes efficient load diffusion and impact hardening through the surface high modulus layer, and the gradual change of interlayer wave impedance promotes the dissipation of stress wave, which significantly improves the safety reserve and dynamic stability of pavement structure. This study verifies the application feasibility of FG-CFRP in high-performance airport pavement engineering, and provides innovative material solutions and theoretical support for the development of a new generation of long-life and high-reliability airport pavement.