Under Impact Loading Caterpillar Vehicles Just Strength Analysis And Optimization

Under the background of an Advance Research Project from the General Armament Department and a National Defense973Project, this thesis is concerned with design and optimization of stiffness and strength for tracked self-propelled gun from static and dynamic aspects by using nonlinear finite element method and topology optimization. The main contents are as below.Firstly, based on the nonlinear finite element theory, nonlinear finite element static and dynamic equations were constructed. Numerical solution method for finite element equations was introduced, in which geometry and material nonlinearity was taken into consideration. In light of structure of tracked vehicle, finite element grid partition method was discussed.Secondly, finite element model of each parts of the vehicle system was established by the modular modeling method, including running system, suspension system and protection system, turret, cradle and barrel. With soil elastic and plastic deformation theory as the foundation, according to tri-axial shear failure experimental data, finite element model of the soil was built. Contact between soil and track, and running system, contact between barrel and cradle, and the geometric nonlinearity of suspension system was modeled respectively.Thirdly, finite element analysis for suspension system was conducted, and then the equivalent stiffness of suspension system was retrieved, which was compared with the calculated result from the classical design theory. Under six different conditions, static stiffness and strength calculation was performed for the vehicle subjected to shock load, and the vulnerable position of the vehicle was found out. Soil model for three representative launch position were established. Dynamic response of tracked self-propelled gun was simulated, and influence of the soil property on muzzle disturbance was investigated. AndFourthly, based on finite element analysis, vehicle optimization design was studied by combination of topological optimization and size optimization. Ensuring the entire vehicle static and dynamic strength, the weight was reduced by12.6%, which showed that the topological optimization effect was obvious.The findings in this paper can be of certain reference to structural design of tracked vehicle.