| During the landing process,the aircraft has a huge impact on the runway surface,the composite coating on the runway surface has a very reliable protective effect on the vulnerable materials and wearable materials,At present,there are few researches on contact impact fatigue of composite coatings,In order to study the impact load that composite coating can withstand under multiple impacts and the life after impact,and further explore the protective effect of composite coating material on airport runway.The researches in this paper are as follows.First of all,this paper analyzes the impact process of aircraft tires on the composite coating when the aircraft is approaching and landing,establish impact models under symmetrical landing and asymmetrical landing conditions and analyze the force of the composite coating to explore the influence of different factors on the impact load of the composite coating,the impact model is numerically solved by MATLAB,and the impact speed,aircraft mass,friction coefficient,and impact angle on impact load under symmetric and asymmetric landing conditions were investigated,and input parameters are provided for simulation analysis.Secondly,Adams was used to simulate the process of tire impact on composite coating,and the influence trend of various factors on impact load under symmetrical landing and asymmetric landing conditions was investigated,and the results were compared with the theoretical results.The nonlinear viscoelastic constitutive model and fatigue life prediction model of composite coating were established based on the basic mechanical experiment and fatigue cumulative damage theory of composite coating.After that,based on the established nonlinear constitutive model and fatigue life prediction model,the fatigue life of composite coating under different working conditions was explored through ANSYS simulation analysis,and the influence trend of landing mode,impact load,impact speed,impact angle,friction coefficient and ambient temperature on the composite coating life was investigated.Through the control variable method,the life changes of dangerous life area and layers under symmetrical and asymmetrical impact are analyzed,and the life distributions of width direction,length direction and thickness direction are obtained.Finally,based on BP neural network model,the life prediction of the composite coating was studied,and the neural network model under symmetric landing and asymmetric landing conditions was established.Levenberg Marquardt algorithm was used to train the neural network to obtain the life prediction results under different conditions.The life prediction results are compared with the simulation results.Both of them are in the reasonable range of error precision,which is verified the correctness and reliability of life prediction research. |
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