Steady-State Dynamic Response of a Bernoulli–Euler Beam on a Viscoelastic Foundation Subject to a Platoon of Moving Dynamic Loads

Abstract

A Bernoulli–Euler beam resting on a viscoelastic foundation subject to a platoon of moving dynamic loads can be used as a physical model to describe railways and highways under traffic loading. Vertical displacement, vertical velocity, and vertical acceleration responses of the beam are initially obtained in the frequency domain and then represented as integrations of complex function in the space-time domain. A bifurcation is found in critical speed against resonance frequency. When the dimensionless frequency is high, there is a single critical speed that increases as the dimensionless frequency increases. When the dimensionless frequency is low, there are two critical speeds. One speed increases as the dimensionless frequency increases, while the other speed decreases as the dimensionless frequency decreases. Based on the fast Fourier transform, numerical methods are developed for efficient computation of dynamic response of the beam.