Residual Mechanical Properties of Slurry Infiltrated Fibre Concrete (SIFCON) Exposed to Freezing and Thawing Cycles

Abstract

Slurry infiltrated fibre concrete (SIFCON), a type of concrete reinforced with fibres (FRC), has a matrix with discrete fibre that lends significant tensile properties to the composite matrix. Generally, FRC contains fibre volume fraction ranging from (1–3) %, while SIFCON has between (4–20) % of fibres. First, SIFCON is created by sprinkling fibres into a mould until it is full. The fibre network is then infiltrated by mortar. The main difference between SIFCON and FRC, in addition to the differences in production method and volume fraction of fibre, is that SIFCON mortar doesn't contain coarse aggregates, which, if used, will prevent the mortar from infiltrating through the network of fibre. This study's major objective is to examine SIFCON's residual compressive strength following exposure to freezing and thawing cycles. Hooked fibres were used with fibre contents of (6, 8.5, and 11) %. In this investigation, hybrid fibre (hooked and microfiber) with a content of 8.5% and microfiber with a content of 6% were also employed. Also, super plasticizers and mineral admixtures were used for SIFCON mortar. Cubic specimens of (100 mm), subjected to 100 cycles of freezing and thawing, are used in this research. Then the samples were tested for compressive strength and compared with those of subjected samples to evaluate the reduction in compressive strength. The results show that the resistance of samples to freezing and thawing cycles increases with increasing steel fibre content. And the specimens with micro steel fibres have higher resistance (lower loss in compressive strength) compared to those containing hooked fibre for the same fibre content.