Overturning Axis Selection in Curved Box-Girder Bridges with Single-Column Piers

Guohua Song,Delu Che,Minghui Li

doi:10.1155/2018/9206138

Abstract

This study was conducted to theoretically analyze the overturning axes of curved box-girder bridges with three equal spans and single-column piers per the influence of curvature radius and bearing eccentricity on overturning axis. The theoretical analysis is verified by a model bridge experiment. The results show that overturning axis can be effectively determined according to the connecting line of either bearings at the central piers or outmost bearings at abutments as influenced by curvature radius and bearing eccentricity. In other words, no bearings are outside of overturning axis. All the bearings but the two on the overturning axis are located on the inner side of the axis. For curved bridges with multispans and single-column or double-column piers, the overturning axis is characterized by the connecting line of the two adjacent outmost bearings.

Highlights

Expanding transportation systems across China have resulted in an impressive number of newly constructed bridges
Bridges with singlecolumn piers are prone to overturning accidents due to their simple boundary conditions [8]
On a small or light curved ramp bridge, overturning moment resistance may suddenly fail to balance out the overturning moment caused by industrial trucks, especially in dense traffic or under heavy loads

Summary

Introduction

Expanding transportation systems across China have resulted in an impressive number of newly constructed bridges. Bridges with singlecolumn piers are prone to overturning accidents due to their simple boundary conditions [8]. In China, the current code JTG D60-2015 [20] has neither specific regulations nor guiding methodology for this purpose This lack of information leaves curved bridges susceptible to poor overturning resistance at the design stage and to overturning accidents at the service stage. Overturning axis by the order of bearing separation; Zhou et al [15] discussed selection of overturning axis of curved bridges under different bearing styles and different curvature radii; Yuan et al [23] found that FSO differs with different overturning axes. Overturning axis selection is effectively the very premise upon which overturning resistance analysis is conducted, which was the focus of the present study on curved bridges with single-column piers

Overturning Axis Selection Principle

Model Setup

Model Making

Selection of Overturning Axis

Verification of Overturning Axis Selection Analysis

Conclusions