RESPONSE TO CONCENTRATED MOVING MASSES OF ELASTICALLY SUPPORTED RECTANGULAR PLATES RESTING ON WINKLER ELASTIC FOUNDATION

The dynamic response to moving concentrated masses of elastically supported rectangular plates resting on Winkler elastic foundation is investigated in this work. This problem, involving non-classical boundary conditions, is solved and illustrated with two common examples often encountered in engineering practice. Analysis of the closed form solutions shows that, for the same natural frequency (i) the response amplitude for the moving mass problem is greater than that one of the moving force problem for fixed Rotatory inertia correction factor R-0 and foundation modulus F-0, (ii) The critical speed for the moving mass problem is smaller than that for the moving force problem and so resonance is reached earlier in the former. The numerical results in plotted curves show that, for the elastically supported plate, as the value of R-0 increases, the response amplitudes of the plate decrease and that, for fixed value of R-0, the displacements of the plate decrease as F-0 increases. The results also show that for fixed R-0 and F-0, the transverse deflections of the plates under the actions of moving masses are higher than those when only the force effects of the moving load are considered. Hence, the moving force solution is not a save approximation to the moving mass problem. Also, as the mass ratio Gamma approaches zero, the response amplitude of the moving mass problem approaches that one of the moving force problem of the elastically supported rectangular plate resting on constant Winkler elastic foundation.