Modeling and Analysis

Uniaxial Compression Behavior of Ultra-High Performance Concrete Confined by Steel Spirals

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Abstract

The superior physical and mechanical behavior of Ultra-High Performance Concrete (UHPC) has attracted lots of interest for large number of applications such as joints and connections. However, there is still a great potential for application of UHPC in large-scale structural elements such as bridge columns. To achiee this goal, design guidelines must be developed which will require a comprehensive knowledge of the confined and unconfined UHPC material behavior. To date, no extensive studies investigated the confining effects of steel spirals on UHPC. This study addresses this gap with a focus on the compressive stress-strain behavior of UHPC cylinders confined using steel spirals. The effect of different volumetric ratios of spirals was investigated and uniaxial compression tests were carried out on the cylinders with 3 in(76 mm) diameter and 6 in(152 mm) height. UHPC cylinders were castfrom one batch, used2%steel fibers ratio, and confined with three different spiral configurations that has 1 in(25 mm), 0.5 in(13 mm),and 0.25 in(6mm)pitch and corresponds 1.9%, 3.8%, and 7.6%volumetric ratio, respectively. The overall behavior ofconfined UHPC cylinders from each group was compared with the reference unconfined UHPC cylinders. Moreover, the out-of-planeness of the tested cylinders along with the actual specimens’ height were reported and related to the compression strength for any trending effects.

Keywords: Compression tests, steel spirals, confinement, uniaxial material response

How to Cite:

Naeimi, N. & Moustafa, M., (2019) “Uniaxial Compression Behavior of Ultra-High Performance Concrete Confined by Steel Spirals”, International Interactive Symposium on Ultra-High Performance Concrete 2(1). doi: https://doi.org/10.21838/uhpc.9663