A local bond stress-slip model for reinforcing bars in self-compacting concrete

The force transfer in reinforced concrete is provided by the concrete-to steel bond. This phenomenon has widely been studied for conventional vibrated concrete (CVC). For self-compacting concrete (SCC) however less test results are available. To fill in this lack and to develop adapted standards for predicting the bond of reinforcement in SCC, an experimental program has been set up. The bond strength of reinforcement bars with different diameters has been tested by means of "beam-test" specimens. During testing the bond stress-slip response was recorded. From the test results it can be seen that the maximum bond strength of SCC is slightly higher than for CVC when small bar diameters are studied. For larger bar diameters the difference becomes smaller. Comparison of the test data with bond models indicated that the bond clauses underestimated the bond strength for SCC as well as for CVC. Therefore an adjustment of the bond model has been made