Research On The Soil-wheel Interaction Model Of Large Transport Aircraft Landing Gear And Numerical Simulation Of Flexible Pavement Bearing Capacity

Large military transport aircraft plays a very important role in modern war and is the direct embodiment of strategic delivery capability.In recent years,with the continuous expansion of functions and missions,the PLA has an urgent need for the construction of the capability of taking off and landing on the flexible pavements of large transport aircraft field airdromes,especially the soil pavement.At present,there is not much research on the theory of interaction between large transport aircraft wheels and soil pavements,and no field airfield or soil pavements construction standards applicable to large transport aircraft have been promulgated.Therefore,it is urgent to carry out relevant research to meet the needs of China’s strategic air force construction.In order to obtain the interaction relationship between the wheels of the main landing gear of large transport aircraft and the soil pavement,and obtain the soil pavement construction standard of field airdrome that meets the requirements of the use of large transport aircraft,the following contents are studied in this paper:1)A theoretical model of "soil pavement-wheel" interaction of large transport aircraft was establishedFor large military transport plane field airdrome runway operation situation of terramechanics by optimizing the soil-wheel interaction theory,considering the pneumatic tire radius equivalent amplification theory,is suitable for large transport aircraft “soil pavement-wheel” interaction theory model,provide the basis for the follow-up the results of numerical simulation and analysis.2)A numerical simulation model of "soil pavement-wheel" interaction of large transport aircraft was establishedEDEM and Recur Dyn were used to build a numerical simulation model of "soil pavement-wheel" interaction of large transport aircraft.The parameters of the model were calibrated by a series of geotechnical tests,and the influence of discrete element particle magnification on the accuracy of the model was discussed.Finally,the feasibility of the simulation model is verified by single wheel model test.3)The numerical simulation of multimodal motion coupling of the main landing gear of large transport aircraft was carried outUsing the established simulation model,the main landing gear of large transport aircraft was simulated in various motion conditions,such as static,uniform motion,takeoff and landing,etc.,and the stress and state changes of the main landing gear wheel and the soil pavement were obtained under various working conditions.4)The evaluation indexes of soil pavement of field airfield are determined and the interaction among them is studiedIn the past,the evaluation indexes of soil pavement did not distinguish service conditions,but only focused on the bearing capacity and thickness of pavement,and the factors considered were not comprehensive enough.According to the use of soil pavement and the numerical simulation results of “soil pavement-wheel” interaction model,the evaluation indexes of soil pavement in different areas under different operating conditions are determined.The evaluation index is more comprehensive than before,and the construction standard of soil pavement which meets the minimum operation conditions of a large transport aircraft is calculated according to the new evaluation index.At the same time,in view of the possible limitations of soil pavement construction site,the interaction between each evaluation index is studied,and more accurate interaction function of each index is obtained.