Free vibration of both-ends clamped wooden beams: is it potentially applicable as an in situ assessment method?

Considerable errors caused by shear deflection and rotary inertia in both-ends clamped flexural vibration make the modulus of elasticity hardly obtainable in flexurally excited beams with similar ending conditions. As both-ends clamped beams and columns are necessarily quality controlled in situ within the building structures, this study has attempted to identify some initial requirements for the dynamic responses of a sound both-ends clamped beam under flexural vibration. Accordingly, the dynamic responses of the both-ends clamped wooden beams in radial and tangential flexural vibration were compared to beams in a free-free condition while stepwise increasing axial compressions were applied to the beams. Both-ends clamped beams had the potential to be subjected to in situ longitudinal Young’s modulus evaluations. The strong correlations among both-ends clamped and free-free beams in terms of evaluated moduli verified the possibility.