Quantum mechanics

Linguistics

Engineering

Philosophy

Buckling

Statistics

Stress (linguistics)

Column (typography)

Computer science

Stress reduction

Physics

Finite element method

Nonlinear system

Database

Psychology

Mathematics

Infill

Psychotherapist

Parametric statistics

Connection (principal bundle)

Structural engineering

Strength reduction

Journal of Structural Engineering

AISC 360-16 (the current AISC Specification) does not endorse the use of high-strength materials (Fy≥525 MPa and fc′≥70 MPa) for concrete-filled steel tube (CFT) columns because of a lack of adequate research and comprehensive design equations. This paper makes a contribution toward addressing this gap and proposes effective stress-strain relationships and design equations for high-strength rectangular CFT members using a three-step method. The first step consists of compiling the experimental database of high-strength rectangular CFT column tests in the literature and evaluating the possibility of extending the current AISC 360-16 design equations to high-strength rectangular CFT short columns. The second step consists of developing and benchmarking detailed three-dimensional (3D) nonlinear finite-element models for predicting the behavior of high-strength CFT columns from the database. The benchmarked models are then used to perform comprehensive parametric studies to (1) address gaps in the database and (2) develop effective stress-strain relationships for modeling the steel tube and concrete infill of high-strength rectangular CFT members, while indirectly accounting for the effects of confinement, yielding, and local buckling. The third step consists of using these effective stress-strain relationships and the enhanced database to propose a new design approach (including equations) for high-strength rectangular CFT short columns. Finally, a reliability analysis is performed to establish a resistance (strength reduction) factor (ϕ) to be used with the proposed design equations.

High-Strength Rectangular CFT Members: Database, Modeling, and Design of Short Columns