The bar buckling behavior is evaluated for different buckling length values and the length is chosen such that it delivers the lowest maximum stress. The proposed model is validated by comparison of the predicted buckling mode with experimental test results from the literature. The average error inthe mode prediction is 0.59 (about half the space between stirrups), which is a reasonably good value considering that the database of tests used covers buckling modes from 1 to 7 (stirrup spacing). Besides of providing good critical buckling length predictions, it allows obtaining the stress versus strain curve for the overall buckling bar