Dynamic Response of a Horizontally Curved Bridge

A method of analysis of the dynamic response of a simple-span horizontally curved bridge subjected to a constant moving force is presented. Differential equations for the out-of-plane vibrational motion of the curved bridge under the action of the constant moving force are derived and solved with the method of initial conditions. The effect of the torsional inertia is studied both in the free vibration solution and in the forced vibration solution. The parameters of the problem are radius of horizontal curvature, rigidity ratio, and speed parameter. The effects of warping and damping are also studied. The significant parameters that describe the behavior of the horizontally curved bridge are the radius of curvature and the rigidity ratio. The effect of changing either of these two parameters results in the change of the fundamental natural frequency of the curved bridge. Under the passage of the constant moving force, the curved bridge is vibrating basically at its fundamental natural frequency.