As can be seen, the PC fully crushed but the CFRC only had visible cracks,
which were held by the coir fibres. Thus, the fibres bridged the adjacent surfaces of the macro-cracks in the concrete and served as an effective secondary reinforcement to impede the development of crack and limit the propagation of cracks by reducing the crack tip open displacement. In turn, the fibre bridging effect contributed
to the increase of axial strain at peak stress and the fracture energy.
It should be pointed here that the alkali treatment has no obvious
effect on the failure pattern of CFRC.