| Abstrakt: |
In this paper, we investigate periodic solutions of a beam equation with jumping nonlinearity. Such a nonlinearity describes the restoring force acting on the bridge due to the possible slackening of the stays of the suspension bridge. By analyzing the beam operator, we find that there is a strictly positive eigenfunction. Thus, for the external force which is a linear combination of the positive eigenfunction and the eigenfunction corresponding to the first negative eigenvalue, using the critical point theory and Brouwer degree theory, we obtain some results on the multiplicity of periodic solutions when the nonlinearity crosses the first negative eigenvalue. [ABSTRACT FROM AUTHOR] |
