Full scale casting of bridges with self-compacting concrete

Self-compacting concrete is capable of filling into corners of formwork through congested reinforcement without causing segregation of coarse aggregate. Investigations of SCC at CBI have achieved a mix design method for self-compacting concrete. Half scale testing of bridge walls at a ready mix station has shown excellent results concerning filling ability, strength and durability (frost resistance and chloride permeability). The mix was composed with W/C below 0.40 and with the use of an air-entraining agent. The results also indicate that the casting process itself is very important. The half scale result was so promising that bridges were selected for full scale casting with self-compacting concrete. In spring 1998, three bridges were cast using self-compacting concrete. For each bridge self-compacting concrete was developed and prequalified regarding strength and durability. The promising results from these bridge castings are reported in this paper.