Influence of Normal Pressure on Bond Strength


  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal


Title: Influence of Normal Pressure on Bond Strength

Author(s): Raymond E. Untrauer and Robert L. Henry

Publication: Journal Proceedings

Volume: 62

Issue: 5

Appears on pages(s): 577-586

Keywords: bond strength, mechanism, normal pressure, pull-out test, reinforced concrete, research, ultimate strength

Date: 5/1/1965

Tests were made on 37 pullout specimens with # 6 and # 9 deformed reinforcing bars having a yield strength of approximately 92,000 psi. All specimens had an embedment length of 6 in. The normal pressure applied to the pullout specimens varied from zero to 2370 psi. Bond strength was found to increase with normal pres-sure in proportion to the square root of the normal pressure when other factors are constant and with the square root of the concrete strength. At ultimate, the bar size had little effect on the ultimate bond strength; however, at loaded-end slips of 0.005 and 0.01 in., the bond strength was greater for the # 9 bar than for the # 6 bar. For both bar sizes, normal pressure increased the bond strength more at ultimate than at lower slips.