Partial Parameter Analysis of the Stability of Small and Medium Span Steel-concrete Composite Bridges

Abstract

Based on a 3 × 35m steel-concrete composite beam bridge of a certain highway project, the finite element software is used to establish a non-linear solid model, and the stability safety factor is used as an evaluation index to perform parameter analysis on the stability and safety of small-span steel-concrete composite continuous beams. The corresponding influence law will be obtained. Except for the width-to-thickness ratio of the compressed flange, the stability and safety of 3 × 35m straight beams are better than those of curved beams in each parameter analysis, and the stability and safety of curved beams is more affected by various structural parameters. For 3 × 35m straight beams, from the perspective of stability, it is recommended to consider the 8.75m beam spacing to save steel. From the comprehensive consideration of structural stability and safety and the amount of steel used, it is recommended that the high-span ratio of medium-small-span steel-concrete composite beams be 1/20. Local buckling will occur in the relatively thin positions of the compressed flange and the web. The value of the width-to-thickness ratio of the compressed flange of a straight beam is suggested.