Analysis of bond stress distribution for prestressing strand by Standard Test for Strand Bond

Strand bond is the unique interaction between prestressing strand and adjacent concrete, and directly affects the performance of the strand in the anchor region. However, strand bond depends upon numerous factors, such as concrete properties and strand surface condition. The Standard Test for Strand Bond (STSB) has been developed to assess the bonding capacity of prestressing strands. Test data are used to propose a bond stress–slip model and investigate the bond stress distribution. The study outcomes are verified by STSB of 0.6 in. (15.2 mm) and 0.7 in. (17.8 mm) strand conducted at the University of Arkansas and collected in the literature. Experimental and analytical results show that the proposed model can predict bond stress versus slippage of prestressing strand within a 2% error. The results also show that the bond stress distribution along the embedment length is not linear or uniform as was assumed by previous researchers.