Stresses in thin-walled beams subjected to a traversing mass under a pulsating force

Abstract

An analytical—numerical method to determine the dynamic response of beams with various boundary conditions subjected to a moving mass under a pulsating force is explained. Governing partial differential equations of the system are changed to a convenience type of ordinary differential equations to be solved through a Runge—Kutta scheme. Pulsating force specifications influenced the dynamic response of the beam depending on the moving mass properties. Results showed the significant effect of the boundary conditions on the dynamic response of the beam, which was considered rarely in the past. Stiffening the constraints reduces the maximum stresses in the beams. Results for identical unsymmetrical beams indicated that stresses in beams would be less when the moving object experiences a stiffer constraint in its start point on the beam. A new extremum value was obtained for the dynamic response of the beam, as the pulsating force on the moving mass oscillates with a special frequency regarded as the main natural frequency of the beam under the moving mass.