A numerical analysis on bending capacity of steel pipe columns using a mechanical joint with concrete-filled steel tube

Abstract

Structural steel pipes have been applied commonly in the bridge construction for foundations or piers with many advantages such as large bending capacity, high shear resistance, and rapid construction. However, site welded joints may face critical technical matters which need to be considered for steel pipe piers during construction stage. Current solutions for pipe joints require the use of high-strength materials with machining technology to ensure accuracy, quality, and increase construction costs with substantial number of joints. Therefore, these solutions, when applied in Vietnam, will also face limitations due to the contractor’s qualification and erection technology at construction site. This study proposes a type of joint for steel pipe piers of viaducts in a mountainous region to eliminate the welding work of the steel pipe at the construction site and to provide high bearing capacity, simple construction, and cost effectiveness. Finite element analyses are conducted to investigate and verify the bending capacity of steel pipes with the proposed joint. Nonlinear material and nonlinear geometry are considered to simulate behaviors of composite action, yielding, and buckling in the structures. Finally, comparative studies of bending capacity of the steel pipe with and without joint are performed. Stress distributions and deformations of the structural components in the joint region are also observed and discussed.