Research On Dynamics And Low-frequency Acoustic Radiation Of Monorail Steel-concrete Composite Track Beam-train Coupling System Due To Slip Effect

In order to investigate the influence of slip effect on the suspended steel-concrete composite track beam-train coupling system,the topic of Research on Dynamics and Low-frequency Acoustic Radiation of Monorail Steel-concrete Composite Track Beam-Train Coupling System Due to Slip Effect is conducted.The equations of motion of steel-concrete composite track beam are derived by analytical method and an improved model for dynamic analysis of steel-concrete composite track beam-train coupling system which has taken the slip effect into account is established by FEM method and multi-body dynamics.A program for solving the equations of motion of the coupling system is compiled based on VB6.0.The influence of slip on dynamic response of suspended steel-concrete composite track beam-train coupling system is studied in detail.The main contents are as follow:(1)According to the mechanical characteristics of the new type of steel-concrete composite track beam,a new model which has taken slip effect,section warping and the separation between the torsion and the shearing center into account is proposed and the energy equations for kinetic energy,potential energy and elastic deformation potential are deduced.Based on the multi-body method,a model with 16 degrees of freedom for the suspended train is proposed by reducing the un-independent freedoms of the rigid bodies.The equations for kinetic energy,potential energy and elastic deformation potential are deduced.(2)An improved disc model for wheels considering tire deformation is proposed by inheriting the advantages of traditional disc contact.The calculation process and formula of the wheel center trajectory are established when the improved model is adopted.Equations of motion for the improved steel-concrete composite track beam-train coupling system are derived based on Lagrange's formula.The solver based on VB6.0 program development platform is developed to solve the time-varying coupling motion equations and investigate the dynamic response of steel-concrete composite track beam-train coupling system induced by tire deformation.(3)The influence of slip effect and other factors such as ratios of curve,velocity and vehicle load on the dynamic response of steel-concrete composite track beam-train coupling system is studied in detail based on the improved model which has taken slip effect and tire deformation into account.(4)General expression for equations of motion for the steel-concrete composite track beam-train coupling system is established and the solver for dynamic responses of the coupling system induced by earthquake is developed.Dynamic response of steel-concrete composite track beam-train coupling system induced by slip effect and other factors such as ratios of curve,velocity and vehicle load under earthquake are studied in detail.(5)Based on the general theory of acoustics and the model of steel-concrete composite track beam-train coupling system considering slip effect,the analysis program for the low-frequency radiation noise of the steel-concrete composite track beam induced by slip effect is developed.By the tools mentioned above,the influence of slip effect and other factors such as velocity and vehicle load on the low-frequency radiation noise is investigated.Through the research of this paper,the very important conclusion presented to us is that the influence of slip effect on the dynamic response and low-frequency radiated noise of steel-concrete composite track beam-train coupling system is very significant.We must give more attention to this conclusion in practice.