STUDY OF THE TRANSFER OF TENSILE FORCES BY BOND.

Results of an experimental and an analytical investigation of bond transfer in reinforced concrete flexural members are presented. To facilitate the measurements of local slip, secondary cracking, and strain distribution in concrete surrounding the interface, a new type of test specimen was developed. For this newly developed specimen, a reinforcing bar was split into two halves and embedded in the opposite sides of the cross section. A comparison of results from these types of specimens with those from the more common tests showed that many of the important aspects of bond transfer phenomena are identical. To enable prediction of secondary cracking, an axisymmetrical finite element analysis was performed. Finally, a simple one-dimensional analysis was developed to predict stresses in steel and concrete, local bond-slip relationships, tensile stiffening, and total elongation of the reinforcing bar.