RC fiber beam–column model with bond-slip in the vicinity of interior joints

• A manner to account for bar bond-slip in the vicinity of interior joints of reinforced concrete elements is proposed.
• We compare experimental results with results obtained following the proposed model.
• The new beam–column finite element is capable of capturing anchorage slippage as well as softening behavior.
• The proposed three-node force-based element accurately predicts nonlinear cyclic behavior.

This paper describes a numerically efficient approach to describe reinforcing bars bond-slip in the vicinity of interior beam–column joints, which is an effect that significantly influences frames behavior regarding stiffness and hysteretic energy dissipation capacity. The fiber-section model proposed here allows for the accurate analysis of those critical regions, taking into account the factors most relevant to the determination of its behavior, without the computational disadvantages of other more complex formulations. The methodology is defined by the fiber model based on continuous anchored bars and by its implementation into a fiber force-based finite element. The behavior of the fiber model based on anchored bars is discussed and then the fiber-section finite element is evaluated by comparison with an experimental test of a beam–column subassemblage subjected to cyclic loading. The proposed beam–column finite element is capable of predicting anchorage slip and the analytical results of the structural subassemblage agree well with the experimental results.