Kinematics And Dynamics Analysis Of Large Complex Structures Under The Action Of Multiple Moving Masses

Large complex structures are widely used in many engineering areas,many of which are subject to multiple moving loads.Such as the roller coaster moving along a large-scale track with a high speed,the impact on the tower during the course of launching,the effect of traveling wave on the support structure of hundred ten million generators boilers and the dynamic load on Fast Radio Telescope Cable Net Structure when Displacement Reflector are rotating.Large-scale structures under multi-moving loads are more likely to deform,generate cracks and destabilize than common structures,which may ultimately lead to the failure of large-scale structures,explosion,and even fire-induced serious consequences.At present,great progress has been made in response analysis or calculation of simple structures under the action of multiple mobile systems.There is no reliable method for calculating the dynamic responses of large and complex structures.In order to solve this problem,this paper presents a new method for calculating the dynamic responses of large and complex structures under multiple moving loads.The specific studies are as follows:(1)The longitudinal vibration responses of simply supported beam under moving system were analyzed.Several types of moving systems are applied to simply supported beams.The influence of type,quantity and speed of the moving system on vibration behavior of simply supported beams is investigated through observing the motion parameters of the middle point on the beam.(2)The movement of multi-body system on the large complex structure was studied.Taking the roller coaster moving in its orbit as an example,the three-dimensional motion equations of the roller coaster are derived.Through the virtual prototype technique,the 3D model of vehicle and its orbital space curve are established,and the high-speed movement of the vehicle on the track is simulated.Through the analysis of various motion parameters,the roller coaster kinematics safety is evaluated.(3)The dynamic responses of complex structures under multi-moving loads were discussed.Taking the roller coaster track,which is under mutip-group fast moving loads,e.g.a finite element model of the roller coaster track is established.The strength,deformation and stability of roller coaster track under multiple sets of high-speed moving loads are discussed.This paper provides a basis for the design of roller coaster track.(4)The application of equivalent statics analysis and transient dynamics in the calculation of the orbit strength of a large roller coaster was introduced.The calculation results of the two methods are compared from many aspects,and the error of equivalent static calculation was analyzed.The applicability of equivalent statics method in the calculation of the strength of large and complex structures was discussed.The present approach can be a helpful tool for engineering to solve the similar problems.The research in this paper is significance for solving the problem of dynamic strength of large-scale space structures and provides data support for the further discussion of the dynamic response of large-scale space structures under multi-moving loads.Meanwhile,it is of guiding significance for the design of large structures subjected to multiple moving loads.