2007 Volume 56 Issue 8 Pages 694-698
High-strength steel strands have been developed using higher strength steel wire rods with higher carbon and silicon contents than conventional steel wire rods. The tensile load of the developed steel strands was 15%∼20% higher than the conventional steel strands : 322kN for 15.2mm diameter strands and 684kN for 21.8mm diameter ones. The developed strands have a fracture elongation comparable to the conventional ones. An increase in carbon concentration and dislocation density resulted in smaller relaxation loss than the conventional strands. The strengthening did not have negative effects on anchoring efficiency of the strands and hydrogen embrittlement. Therefore, special operations are not required for practical use of the developed high strength steel strands. Their higher-strength is expected to reduce the materials used for prestressed concrete members, to decrease the weight of concrete members, and shorten the construction period.
