Abstract

Previous studies proved that the application of FRP can eliminate some unwanted properties of high-strength concrete, such as the brittle behaviour of high-strength concrete. However, research studies conducted so far on external confinement of concrete columns have mainly concentrated on concentric loading. This paper experimentally investigates the performance of externally confined high-strength concrete columns subjected to eccentric loading and evaluates the effectiveness of two confinement materials-carbon fibre and E-glass. Plain columns were wrapped with either carbon fibre or E-glass with different number of layers. Two reference columns were internally reinforced and tested. The enhancement of the strength of the plain column specimens under eccentric loading is not so pronounced as for the concrete specimens under concentric loading, especially for the high strength concrete specimens. However, when wrapped, the columns achieved a considerable gain in strength compared to plain concrete columns.

Author Keywords: External confinement; High-strength concrete; Fibre-reinforced polymers; Eccentricity; FRP; Carbon fibre; E-glass

Article Outline

1. Introduction

2. External confinement with FRP

2.1. FRP wrapping configurations

2.2. Modelling of FRP confinement

2.3. Confinement effectiveness

3. Preliminary testing

3.1. Introduction

3.2. Tensile testing of FRP

3.2.1. Specimen preparation and testing

3.2.2. Testing results

4. Experimental program

4.1. Column’s details

4.2. Eccentric loading

4.3. Specimen preparation

4.4. Test specimens

5. Observed behaviour and test results

5.1. Internally reinforced columns

5.2. E-glass wrapped columns

5.3. Carbon wrapped columns

6. Comparisons and analysis

7. Theoretical calculations

8. Conclusions

Acknowledgements

References