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Self-compacting concrete (SCC) has different properties compared with the normal concrete regarding its fresh and mechanical behaviour. A number of studies have been carried out to determine
the benefits of incorporating various cement replacement materials into the self-compacting concrete.
These materials reduce the cost of the SCC resulting from the significant amount of cement that is
necessary to provide the required SCC flow ability. Decreasing or eliminating the use of cement in
SCC seems imperative for both economical and environmental reasons. This study investigates fresh,
mechanical and fracture properties of sustainable SCC in which 86% of the cement is replaced by
ground granulated blast furnace slag (GGBS) with six different polypropylene and basalt fiber volume
fractions (Vf = 0%; 0.025%; 0.05%; 0.075%; 0.125%; 0.25%) within an identical SCC matrix. The
water to binder (w/b) ratio of SCC mixtures is maintained at 0.32. Two aspects of fresh SCC properties
including filling ability (slump flow, T500) and passing ability (L-box) of the mixtures have been investigated. SCC with fiber reinforcement fulfil the fresh concrete properties requirements of the EFNARC
guideline. In this research, the compressive, tensile splitting and flexural strengths of fiber reinforced
SCC have also been compared with plain SCC. The study proposes empirical relationships to predict
28-day compessive, tensile splitting and flexural strengths based on 7-day strengths, respectively. In
addition, the fracture properties of various sustainable fiber reinforced SCC mixtures were determined at
7 and 28 days after the moist curing of concrete. The higher amount of basalt and polypropylene fiber
resulted in an improvement of strengths, flexural toughness, fracture energy and rigidity of the SCC
up to 0.25 vol.% of fibers and thus, the use of these fibers would enhance overall SCC performances.
The experimental studies show that fiber reinforced SCC with the use of GGBS as 86% replacement
to the cement weight is potentially a sustainable alternative construction material. The mechanical
and fracture properties of the sustainable SCC mixtures containing fibers falls within ranges suitable for structural engineering applications.
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