Mechanical properties of steel fiber reinforced high strength lightweight self-compacting concrete (SHLSCC)

• Steel fiber reinforced high strength lightweight self-compacting concrete is developed.
• Effect of change in short straight steel fibers content on fresh and hardened concrete properties is studied.
• Workability, air content and compressive strength decrease with increase of fiber content.
• Tensile strength, flexural strength and toughness increase significantly with increase of fiber content.
• Concrete exhibits strain hardening behavior at fiber content of 0.75% and more.

With addition of steel fibers to concrete, its properties are altered from brittle to ductile. Using lightweight concrete enables decrease in additional loads while self-compacted concrete avoids use of vibrators for concrete compaction, in case of renovation or/strengthening of existing structures. This study is aimed at investigating the effect of change in micro steel fiber content on the properties of steel fiber reinforced high strength lightweight self-compacting concrete (SHLSCC). Slump flow test was conducted to find the workability of fresh concrete mixture. Further compressive strength, splitting tensile strength, modulus of elasticity and flexural strength of hardened concrete were tested. Five concrete mixes of SHLSCC with different fiber contents (0%, 0.5%, 0.75%, 1% and 1.25%) were prepared to study the change in its fresh and hardened properties. Results show that there is strong influence on the workability of SHLSCC with steel fiber content of 1% or more. There is around 12% reduction in compressive strength, 37% and 110% increase in splitting tensile strength and flexural strength respectively, with increase of steel fiber content from 0% to 1.25%, while the modulus of elasticity remains unchanged.