Title: Bond Properties of High Strength, Low Carbon Bars with Drawn-in Helical Deformation for Use in Pretensioning and as Special Normal Reinforcement

Author(s): M. Schupack and K. Mizuma

Publication: Journal Proceedings

Volume: 76

Issue: 2

Appears on pages(s): 249-276

Keywords: bond (concrete to reinforcement); concrete piles; deformed reinforcement; flexural strength; post-tensioning; prestressed concrete prestressing steels; pretensioning; stress transfer.

DOI: 10.14359/6946

Date: 2/1/1979

Abstract:
A drawn, helically grooved, low carbon, induction heat-treated prestressing steel has been developed and used extensively in Japan for over 10 years. This steel has unique physical and bond characteristics. Over 430,000 metric tons of this type of steel have been used to date in Japan, mostly in prestressed concrete cylinder piles. The paper describes the bond characteristics of the steel determined by pullout tests, bond transmission tests, and flexural bond tests. The tests indicate that for an 11 mm bar of this type, bond characteristics are similar to a 7/l 6 in. seven-wire strand which has comparable ultimate strength.