6% steel fibre content

3% steel fibre content

Placeability

Because of the fluidity and cohesiveness of the matrix, the material is easily placed - even with large fibre contents and with little room between reinforcing bars. The water/powder ratio is typically in the range 0.15-0.20 and while the CRC-matrix can be classified as a Self Compacting Concrete (SCC) it responds well to vibrations. In-situ cast connections between precast beams and slabs are typically produced with 6% of fibres, while balcony slabs and staircases are typically produced with 2-3% of fibres. Slump cone test results of 6 and 3% of fibres are shown in the pictures.
   

The slump cone test is not very suitable for assessing the workability of fibre reinforced concrete, but it gives some indication of the amount of vibration needed to achieve proper consolidation. In quality control a flow measurement is used.