VIBRATION ANALYSIS OF BEAMS TRAVERSED BY UNIFORM PARTIALLY DISTRIBUTED MOVING MASSES

An investigation into the dynamic behavior of beams with simply suppor ted boundary conditions, carrying either uniform partially distributed moving masses or forces, has been carried out. The present analysis i n its general form may well be applied to beams with various boundary conditions. However, the results from the computer simulation model gi ven in this paper are for beams with simply supported end conditions. Results from the numerical solutions of the differential equations of motion are shown graphically and their close agreement, in some extrem e cases, with those published previously by the authors is demonstrate d. It is shown that the inertial effect of the moving mass is of impor tance in the dynamic behavior of such structures. Moreover, when consi dering the maximum deflection for the mid-span of the beam, the critic al speeds of the moving load have been evaluated. It is also verified that the length of the distributed moving mass affects the dynamic res ponse considerably. These effects are shown to be of significant pract ical importance when designing beam-type structures such as long suspe nsion and railway bridges. (C) 1995 Academic Press Limited