Prestress Force Effection on Natural Frequencies of Simply Supported Beams

Abstract

Natural frequencies of bridges have certain sensitivity to prestressing force, so the identification of effective prestressing force based on bridges' natural frequencies is a effective method. This paper uses Finite Element Methods to establish the finite element model of prestressed steel beam, and then conducts dynamic simulation analysis of the natural frequencies of the simply-supported bridges on the condition of different prestressing forces and different reinforcement eccentricity distance arrangements. Based on the results, it analyzes the law and the extent of prestressing force's influence on the natural frequencies, and at last makes the quantitative relation of the prestressing force and the natural frequencies of the bridges. It supplies the theoretic support for the identification of effective prestressing force in the prestressed simply supported beams.