Title: Bond characteristics of untensioned prestressing strand
Date: January-February, 1977
Volume: 22
Issue: 1
Page number: 52-65
Author(s): John R. Salmons, Timothy E. McCrate
https://doi.org/10.15554/pcij.01011977.52.65
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Abstract
The bond behavior of untensioned prestressing strand was studied to evaluate load-deformation characteristics as well as load-embedment requirements. The results of the study are applicable to bonded untensioned strand as reinforcing for concrete in particular for connection between precast elements. Three strand configurations were studied, namely, straight, frayed and bent 90 deg over a reinforcing bar. Relations were developed between loaded end slip and applied steel stress from test data for each configuration. Design equations were developed which relate the embedment length necessary to insure against general slippage for a given steel stress. Both working stress and ultimate strength equations, which account for a variation of pre-bond length for the bent strand configuration, are presented. The influence of strand diameter, concrete strength, and containment reinforcing were also studied and found to be of little consequence.
References
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