Theoretical and Numerical Study on Dynamic Characteristics of Composite Trough Girder with Corrugated Steel Webs

Abstract

The trough girder with corrugated steel webs (TGCW), introduced to overcome the inherent limitations of traditional trough bridges, is an innovative steel-concrete composite bridge form consisting of a concrete bottom slab, two corrugated steel webs (CSWs), and a pair of concrete top flanges. The natural vibration characteristics, as the fundamental basis for dynamic analysis, are of great significance for bridge design. However, previous studies were limited to the statistical behaviors of this new bridge form. In this article, a general analytical model applicable to the dynamic behavior of a TGCW was developed based on the energy variation principle and Hamilton theory. Natural frequencies and mode shapes accounting for the coupling effect considering the shear deformation of the TGCW, the shear lag effect of the TGCW bottom flange, and the stiffness correction of CSWs were obtained through the analytical formulas. By comparing the theoretical values and the results of finite element analysis, the correctness of the proposed formulas is verified. Differences in the fundamental frequencies calculated through different analytical formulas are discussed. Sensitivity studies were conducted to address the effects of span length, bottom flange width, CSWs waveform and thickness on the vibration frequencies, and mode shapes of TGCW through finite element analysis.