The introduction of various kinds of Fibre Reinforced Concrete (FRC) has brought a new dimension in structural performance in the last few decades. The results obtained with Strain Hardening Cement Based Composite (SHCC) show improved performance especially in terms of…
The introduction of various kinds of Fibre Reinforced Concrete (FRC) has brought a new dimension in structural performance in the last few decades. The results obtained with Strain Hardening Cement Based Composite (SHCC) show improved performance especially in terms of tensile ductility and accompanied multiple cracking, and potentially reduced water and gas permeability and effective chloride diffusivity in the cracked state. Most of the published results for SHCC are based on SHCC with fine silica sand. For construction work fine silica sand is not freely available in South Africa and as a result it is often expensive to use it. Preliminary research on SHCC with coarse sand shows that it is possible to obtain more than 3% tensile strain, but up to and beyond 5% strain for SHCC with fine sand. However, a strain capacity of more than 1% will be sufficient for many applications. So, this paper reports on a research project in which SHCC with a maximum size of 300 µm of fine sand and 2.36 mm of coarse sand respectively, were developed. Dumbbell specimens were used in direct tensile tests and beam specimens were used to study chloride penetration in cracked SHCC, for both fine and coarse grained SHCC. Cracks in beam specimens were formed by flexural testing, after which chloride attack was simulated by cyclic wetting and drying with NaCl solution respectively to study the chloride penetration profiles caused by these exposures. Conclusions are drawn on the resistance to chloride penetration of fine and coarse grained SHCC under such simulated chloride exposure(s) in the cracked state.