Full-scale pipes using dry-cast steel fibre-reinforced concrete

The mechanical properties of dry-cast steel fibre-reinforced concrete (DCSFRC) were investigated in the present study. Four commercially available steel fibres were added at rates of 0, 20, 40 and 60 kg/m3. Full-scale 300 mm diameter precast pipes were fabricated using the tested DCSFRC mixtures to examine its potential for such application. In addition, plain (PC) and conventionally reinforced concrete (RC) precast pipes were fabricated and tested for comparison. As expected, results showed that the mechanical properties of DCSFRC were enhanced as the fibre dosage increased. Generally, hooked-end fibres with the highest aspect ratio led to highest tensile and flexural strengths. Furthermore, DCSFRC precast pipes achieved ultimate loads greater than the required strength for Class V pipes according to the ASTM C76 standard. The post-peak behaviour of DCSFRC pipes was comparable or superior to that of conventional RC pipes. Findings of this research indicate that discrete steel fibres could be an adequate alternative to the labour intensive and time-consuming steel cages normally used for reinforcing precast concrete pipes.