MECHANICAL PROPERTIES OF A HIGHLY FLOWABLE ULTRAHIGH- PERFORMANCE FIBER-REINFORCED CONCRETE MIXTURE CONSIDERING LARGE-SIZE EFFECTS

Author(s): P. Aghdasi, G. Palacios, A.E. Heid and S.-H. Chao
Book Title: Seventh International RILEM Conference on High Performance Fiber Reinforced Cement Composites (HPFRCC7)
Editor: H.W. Reinhardt, G.J. Parra-Montesinos, H. Garrecht
ISBN: 978-2-35158-145-2
e-ISBN: 978-2-35158-146-9
Publisher: RILEM Publications SARL
Publication year: 2015
Pages: 193-200
Total Pages: 8
Language: English

Abstract: This paper discusses the development of a highly flowable ultra-high-performance fiber-reinforced concrete (UHP-FRC) having 200 MPa compressive strength with high compressive and tensile ductility. The methodology uses a dense particle packing and particle shape mechanism to enhance the flowability. The latter was achieved by introducing a suitable amount of fly ash. Fly ash can decrease the possibility of thermal cracking by reducing the heat of hydration, which is critical for large-scale structural applications of UHP-FRC. Most research on mechanical properties of UHP-FRCs has been based on small batch mixing resulting in small-scale specimens. This research addresses large-size effects on UHP-FRC mechanical properties by performing compressive strength and tensile tests using larger-scale material specimens. The size effect of two different sized tensile specimens was investigated. It is well-known that the presence of reinforcing bars can affect concrete’s mechanical properties; therefore, the tension-stiffening effect on reinforced UHP-FRC was also investigated. Finally, this research was concluded by a large-scale casting experiment in which 0.62 cubic meter of UHP-FRC was produced and used in part of a full-scale moment frame column. Mechanical properties of the full-scale UHP-FRC column were collected to compare with those results obtained from small-scale material testing. Modulus of elasticity of the developed UHP-FRC was measured, which is of great importance in controlling deflection under service loading.

Online publication: 2015
Publication Type: full_text
Public price (Euros): 0.00