3 research outputs found
A direct method for analyzing the nonlinear vehicle–structure interaction
This article presents an accurate, efficient and stable algorithm to analyze the nonlinear vertical
vehicle-structure interaction. The governing equilibrium equations of the vehicle and structure are
complemented with additional constraint equations that relate the displacements of the vehicle with the
corresponding displacements of the structure. These equations form a single system, with displacements
and contact forces as unknowns, that is solved using an optimized block factorization algorithm. Due to
the nonlinear nature of contact, an incremental formulation based on the Newton method is adopted. The
vehicles, track and structure are modeled using finite elements to take into account all the significant
deformations. The numerical example presented clearly demonstrates the accuracy and computational
efficiency of the proposed method
Wheel–rail contact formulation for analyzing the lateral train–structure dynamic interaction
A wheel-rail contact formulation for analyzing the train-structure nonlinear interaction that takes into
account the wheel and rail geometry is proposed. Most of the existing methods treat the contact forces as
external forces, whereas the present formulation uses a finite element to model the behavior in the contact
interface, based on Hertz's theory and Kalker's laws. The equations of motion are complemented with
constraint equations that relate the displacements of the vehicle and structure, being the complete system
solved directly using an optimized algorithm. The formulation is validated with experimental data from a test performed on a rolling stock plant
A direct method for analyzing the vertical vehicle-structure interaction
A new method for the dynamic analysis of the vertical vehicle-structure interaction is presented. The
vehicle and structure systems can be discretized with various types of finite elements and may have any
degree of complexity. The equations of both systems are complemented with additional compatibility
equations to ensure contact between the vehicles and the structure. The equations of motion and the
compatibility equations form a single system that is solved directly, thus avoiding the iterative procedure
used by other authors to satisfy the compatibility between the vehicle and structure. For large structural
systems the proposed method is usually more efficient than those that frequently update and factorize the
system matrix. Some numerical examples have shown that the proposed formulation is accurate and
efficient