Bond strength prediction for plain bars under lateral tensile compressive stresses Available to Purchase

The bond strength of plain bars plays an important role in assessing the anchorage capacity of historical buildings. For plain bars, the bond strength greatly depends on the frictional effect, and can easily be affected by the lateral stress around the bars. For bars located in the beam–column joint, the lateral compressive–tensile stresses from gravity and earthquakes might be applied simultaneously. To date, the effect of such biaxial stresses on the bond strength of plain bars has not been evaluated in an analytical manner. Consequently, an analytical approach combining both theoretical and numerical solutions to the bond strength of plain round bars under biaxial tensile compressive stresses is developed. Comparison between test data and the results calculated by the proposed analytical model shows that the model is well capable of predicting the bond strength for different concrete and bars. Moreover, the comparative studies between the proposed analytical model and closed-form solutions show that the partial separation of the bond interface due to the biaxial stresses cannot be ignored in predicting the bond strength of plain bars. Finally, a simplified model with acceptable precision is suggested to substitute for the numerical procedure in the proposed analytical model.