A bonding damage detection method with force-based beam element

Bonding damage of steel bar in beams leads to severe degradation of load transferring capacity which usually affects the performance of the construction. However, bonding damage is difficult to detect because of its characteristics. It is generally known that force-based finite elements are superior to stiffness-based finite elements due to the fact that the force interpolation functions can reproduce the variation of elemental internal forces accurately. In this paper, a force-based beam finite element is formulated and a bonding damage detection methodology based on this element is proposed. A concrete beam reinforced with steel bar under a static load is investigated numerically. The bonding damage can be detected with the proposed method. The analysis results also show that the force-based element is one of the most practical and efficient finite element models that can represent the bonding damage of steel bars in the beam very accurately.