Influence of Micro/ Hooked Steel Fibre Dosage on Concrete Mechanical Characteristics

  • Mohammed R. Abdul Amir, Rafea F. Hassan

Abstract

The effect of steel fibre type, dosage and gravel maximum size on the mechanical characteristics of steel fibre reinforced concrete (SFRC) were investigated in this study. The experimental results demonstrate that the compressive strength, flexural strength, and splitting tensile strength of (SFRC) increase as steel fibre percentage increases. It is found that the compressive strength was influenced by steel fibre kind. It is  also found that the increase of gravel maximum size in (SFRC), was reduced the mixture slump, and the compressive strength was reduced by increasing the gradation of the gravel that used  in (SFRC) for both kinds of steel fibre(micro,hooked end). In this study, three gravel maximum size were utilized in (SFRC) mixtures(10 mm, 14 mm, and 19 mm). Two kinds of steel fibre were used) micro steel fibre (length 13 mm and diameter 0.2 mm),and hooked end steel fibre (length 35 mm and diameter 0.55mm),  with three-volume fractions of fibres (0.5%, 1%, 1.5%). Twenty-one concrete mixes were prepared and investigated. When the micro-steel fibre and gravel maximum size (10 mm)wereutilized in preparing the mixtures of (SFRC), the compressive strength of (SFRC) increased by 29% for 0.5% volume fractions of fibres, and increased by 57.7% for 1% and this increasing wasabout 62.4% for 1.5% volume fractions of fibres. By using the hooked steel fibre and gravel maximum size (10 mm) in preparing the mixtures of (SFRC),  and for the same fibervolume fractions (v.f), the compressive strengthof (SFRC) increased by about(19.7%,28%,47.8%) for the volume fractions of steel fibre (0.5%, 1%, 1.5%), respectively. When using gravels with maximum size 14 mm with the same percentages of micro- steel fibre, theincreasing  results in the concrete's compressive strength were about (50%, 75% and 84%)for the volume fractions of steel fibre (0.5%, 1%, 1.5%), respectively. While when using hooked steel fibres, The rate of development in compressive strengthof (SFRC) was about(10.5%, 23% and 30%), for the same volume fractions of steel fibre ( 0.5%, 1%, 1.5%). Flexural strength of  (SFRC) was also developed, by using gravels with maximum size (10 mm), This development recorded a growth of about 64.5%, 95% and 100% for ( 0.5%, 1%, 1.5%)volume fractions ofmicro-steel fibres respectively,and recorded 6%, 54%, and 99% for the same percentages of hook steel fibres.

Published
2021-10-21
How to Cite
Mohammed R. Abdul Amir, Rafea F. Hassan. (2021). Influence of Micro/ Hooked Steel Fibre Dosage on Concrete Mechanical Characteristics. Design Engineering, 5882 - 5897. Retrieved from http://thedesignengineering.com/index.php/DE/article/view/5550
Section
Articles