Vibration-based estimation of axial force for a beam member with uncertain boundary conditions

Focusing on the application for diagonal braces, tie-bars and short thick cables, this work proposes a new technique to identify the axial force of a two-dimensional Euler–Bernoulli beam member. Bending stiffness effects are taken into account. On the basis of the dynamic measurements from at least five sensors, the proposed method is capable of estimating the axial force as well as the translational and rotational stiffness at both beam ends. When fixing some end constraints, the required number of sensors can be reduced. Finite element simulations are performed for verification purpose, accounting for a wide range of bending stiffness. A laboratory experiment is conducted to investigate the feasibility and accuracy of the proposed method.