Slipforming with fiber-reinforced concrete for efficient crack control

The paper presents the results of slipforming field trials carried out to investigate the potential of polypropylene fibre reinforced concrete in reducing the need for anti-cracking conventional reinforcement in slipform construction. Three trials are reported in which polypropylene fibre reinforced concrete of different strengths ranging between 43 and 54 N mm-2 was used to replace conventional reinforcement in normal concretes. In addition steel fibre (melt-extract) reinforced concrete of strength 60 N mm-2 was also used in one of the trials. In order to achieve optimum mix design, use was made of pulverized fuel ash, silica fume and admixtures such as superplasticizer, retarder and air entrainer as required. The results of the field trials confirm the promising potential of fibre-reinforced concrete in eliminating the need for conventional anti-cracking reinforcement in slipform construction.