Title: Bond Stress-The State of the Art

Author(s): ACI Committee 408 Phil M. Ferguson (chairman)

Publication: Journal Proceedings

Volume: 63

Issue: 11

Appears on pages(s): 1161-1190

Keywords: ACI committee report, anchorage, bond, bond stress, building codes, lightweight aggregate concrete, reinforced concrete, reinforecment, steel

DOI: 10.14359/7665

Date: 11/1/1966

Abstract:
The nature of bond failure is discussed and the influence of splitting is emphasized. The large bond stresses adjacent to any crack and the complications caused by this "out-and-in" bond are emphasized. Factors influencing splitting and the weak planes in splitting are related. The importance of beam width or bar spacing on bond resistance is developed. The concepts of end anchorage, flexural bond, and anchorage or development bond are contrasted. Present knowledge of bond behavior and the absolute value of bond resistance are reviewed, first in terms of splices and special members, and then in the negative movement region of a beam. Some of the data justifying the 1963 Building Code provisions are presented. The value of end anchorage is indicated and the importance of development bond or development length is emphasized. The effect of top bar position and the influence of light-weight concrete are briefly discussed. Finally, weak spots in existing knowledge and areas needing further investigation are mentioned.