Behavior of Confined High Strength Concrete Columns under Axial Compression

Abstract

An experimental study was carried out to investigate the behavior of high strength concrete short columns confined by circular spirals and square ties under monotonically increasing concentric compression. The test variables included volumetric ratio, spacing and yield strength of transverse reinforcement, longitudinal reinforcement ratio, lateral steel configuration, shape of cross section and concrete compressive strength. The effects of these variables on the uniaxial behavior of high strength concrete columns are presented and discussed The results indicate that more confinement is required in columns of high strength concrete than in columns of low strength concrete to achieve the desired post-peak deformability. The behavior of high strength concrete columns is characterized by the sudden spalling of concrete cover, leading to a loss of axial capacity. A comparative study of existing confinement models of high strength concrete columns was also conducted to assess their capabilities of predicting the actual test behavior. To this end, the stress-strain curves of the specimens tested in the present study were compared with the ones predicted by the various models. It is shown that Legeron & Paultre (2003) model estimates the actual experimental curves more closely as compared to the other models employed in the study.

Numerical simulation of conventional RC columns under concentric loading

“…Sharma et al [11] investigated the behavior of short tied columns of high strength concrete under concentric compression. The effects of volumetric ratio, longitudinal reinforcement ratio, lateral steel configuration, shape of cross-section and concrete compressive strength were evaluated and discussed.…”

“…Over the last five decades, many experimental studies have been carried out by researchers to predict stress-strain law of normal and high strength RC columns confined with conventional reinforcement under compressive loading [9][10][11][12][13][14][15][16][17][18][19]. Sharma et al [11] investigated the behavior of short tied columns of high strength concrete under concentric compression.…”

Derivation of Complete Stress–Strain Curve for SSTT-Confined High-Strength Concrete in Compression

“…Such energy is relatively larger when dealing with high-strength concrete. Several solutions have been proposed to eliminate or reduce the interaction issue, e.g., control strain pace at a very low level to prevent sudden disintegration of the specimen and machine, or use steel cylinder in parallel with concrete test specimen to reduce the sudden release of strain energy from the machine during the entire test [14][15][16][17][18][19][20][21]. Nevertheless, even if the interaction problem was solved, the challenge in recording the descending branch of the stress-strain curve beyond the ultimate strength remains unsolved.…”

Flexural capacity enhancement of rectangular high‐strength concrete columns confined with post‐tensioned steel straps: experimental investigation and analytical modelling

“…The failure of unconfined HSC members is more explosive and sudden. Against this background, a number of studies have been conducted to investigate confined columns with HSC Most of these tests have mainly concentrated on confinement methods using fibre‐reinforced polymer (FRP).…”