Periodic Solutions of the Euler–Bernoulli Quasilinear Vibration Equation for a Beam with an Elastically Fixed End

We consider the problem about time-periodic solutions of the quasilinear Euler–Bernoulli vibration equation for a beam subjected to tension along the horizontal axis. The boundary conditions correspond to the cases of elastically fixed, clamped, and hinged ends. The nonlinear term satisfies the nonresonance condition at infinity. Using the Schauder principle, we prove a theorem on the existence and uniqueness of a periodic solution.