PHYSICAL AND GEOMETRICAL NONLINEAR DYNAMIC ANALYSIS OF BEAMS ON FOUNDATIONS UNDER MOVING LOADS

Abstract eng:
The vibration of beams on foundations subjected to moving loads is an important engineering problem, namely in high-speed railway track design; for some (critical) velocities of the load, the beam’s oscillation amplitudes may become very large thus endangering the structural and passengers safety. This presentation is dedicated to the finite element analysis of the behavior of Euler-Bernoulli beams on foundations under moving loads. The goal of this study is to generalize, for more realistic foundation behaviors, the analyses performed by other authors so that it could be useful in railway track design. Thus, the foundations are considered to be tensionless (null tensile stiffness) while under compression their reaction force depends on the transverse displacement of the beam according to a cubic law. The consideration of tensionless foundations leads to large deflections of the beam. Consequently, the finite element formulation of the problem is derived taking into account the geometrical nonlinear behavior of the beam and the semi-discrete system of dynamic governing equations is solved by the HHT-alpha method. Critical velocities of the moving loads are computed and the effect of the physical and geometrical nonlinear behavior of the system on their values is analyzed.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket