Uniaxial compression tests for ultra-high performance hybrid steel fiber reinforced concrete (UHPC) were performed to evaluate the compressive behavior of UHPC. The UHPC for testing contains hybrid steel fibers with a predetermined ratio using a length of 19 mm and 16 mm straight typed steel fibers. Test parameter was determined as a fiber volume ratio to investigate the effect of fiber volume ratio on the strength and secant modulus of elasticity. Test results showed that the compressive strength and elastic modulus of UHPC increased with increasing the fiber volume ratio. Based on the test results, the compressive strength and modulus of elasticity equations were proposed as function of the compressive strength of unreinforced and fiber reinforced UHPC, respectively. The simplified equations for predicting the mechanical properties of the UHPC were a good agreement with the test data. The proposed equations are expected to be applied to the SFRC and UHPC with steel fibers.
ultra-high performance concrete;steel fiber;stress-strain relationship;compressive strength;modulus of elasticity;
Kang, S. T., Park, J. J., Ryu, G. S., and Kim, S. W., "The Effect of Steel-Fiber Reinforcement on the Compressive Strength of Ultra High Performance Cementitious Composites (UHPCC)", Journal of the Korea Institute for Structural Maintenance and Inspection, Vol.14, No.5, 2010, pp.110-118.
Kang, S. T., and Ryu, G. S., "The Effect of Steel-Fiber Contents on the Compressive Stress-Strain Relation of Ultra High Performance Cementitious Composites (UHPCC)", Journal of the Korea Concrete Institute, Vol.23, No.1, 2011, pp.67-75.
Kang, S. T., "Comparison of Flexural Tensile Strength according to the Presence of Notch and Fiber Content in Ultra High Performance Cementitious Composites", Journal of the Korea Concrete Institute, Vol.24, No.5, 2012, pp.525-533.
Association Francaise du Genil Civil (AFGC) Betons fibres aultra-hautes performances. Association Francaise du Genil Civil, 2013, France.
Korea Concrete Institute, Design Recommendations for Ultra-High Performance Concrete K-UHPC, KCI-M-12-003, Korea, 2012 (in Korean).
Fanella, D. A., and Naaman, A. E., "Stress-Strain Properties of Fiber Reinforced Mortar in Compression", ACI Journal, Vol.82, No.4, 1985, pp.475-483.
Ezeldin, S., and Balaguru, P. N., "Normal- and High-strength Fiber-Reinforced Concrete Under Compression", ACI Material Journal, Vol.94, No.4, 1997, pp.286-290.
Nataraja, M. C., Dhang, N., and Gupta, A. P., "Stress-Strain Curve for Steel-Fiber Reinforced Concrete Under Compression", Cement & Concrete Composites, Vol.21, 1999, pp.383-390.
Song, P. S., and Hwang, S., "Mechanical Properties of High- Strength Steel Fiber-Reinforced Concrete", Construction and Building Materials, Vol.18, 2004, pp.669-673.
Yazici, S., Inan, G., and Tabak, V., "Effect of Aspect Ratio and Volume Fracture of Steel Fiber on the Mechanical Properties of SFRC", Construction and Building Materials, Vol.21, 2007, pp.1250-1253.
Hsu, L. S., and Hsu, C. T., "Stress-Strain Behavior of Steel-Fiber High-Strength Concrete Under Compression", ACI Structural Journal, Vol.91, No.4, 1994, pp.448-457.