Concrete columns with discrete confinement by metal sheets subjected to uniaxial compression: derivation toward design rule

Abstract

This paper applied a nonlinear finite element model to study the effect of discrete metal sheet confinement on the uniaxial compressive strength of concrete columns. The columns in this study had circular cross sections with a diameter of 15 cm and a height of 75 cm. Concrete columns with various discrete wrap patterns were computationally simulated and found to be consistent with available experimental results. The results from the three-dimensional finite element modelling showed the effect of the bi-axial response of the metal sheet when it acted as confining material. An analytical procedure outlined in this study was used to determine the effective confining pressure in concrete. This work demonstrates that the development of the strength of a concrete column with discrete metal sheet confinement depends on its size, spacing and the number of the applied metal sheet layers. Strength prediction equations for study columns were derived as an example adaptable to formulate necessary design rules.

Keywords

• Concrete
• Metal sheet
• Axial compression
• Finite element analysis
• Confinement