Steel fibre reinforced concrete
Steel fibre reinforced concrete (SFRC) has been investigated in academia for more than 50 years. The addition of fibres aims at reducing the brittleness of plain concrete by transmitting stresses across cracks. However, its use in construction practice is limited to few, typically non-structural applications. The main reason for this limited use is the inherent softening behaviour of SFRC after cracking: The practically feasible steel fibre content is limited by the workability of the concrete mix, and standard fibre contents, therefore, result in a tensile capacity of the fibres below the cracking load of the concrete (the load immediately drops after cracking in a deformation-controlled experiment). Furthermore, the fibres are typically pulled out of the matrix, resulting in a softening post-cracking behaviour even if the fibre capacity exceeds the tensile strength of the concrete.