Quasi-hinge beam element implemented within the hybrid force-based method

• A new hybrid force-based solution method is followed.
• A general beam element is proposed.
• Quasi-hinge and refined hinge element are compared.

This paper describes a new force-based hinge element implemented in the framework of the Large Increment Method (LIM). The element can be of arbitrary cross section and is capable of including inelastic behaviour close to structural hinges. The element formulation can accommodate elasto-plastic strain hardening material behaviour. The solution procedure involves the analysis of elastic and inelastic deformations separately facilitated by splitting of the element length into elastic and inelastic zones. Deformation is calculated by considering inelastic behaviour in the element volume close to both ends of the structural member using an optimum number of integration points in order to achieve good accuracy while maintaining computational efficiency. The predictions of both conventional- and quasi-hinge elements are compared against predictions from Abaqus™. Predictions of the quasi-hinge element show significant improvements over the conventional-hinge method and are shown to converge on the Abaqus™ prediction as the number of monitoring sections in the element is increased.