ON THE EFFECTS OF HIGHER VIBRATION MODES IN THE ANALYSIS OF 3-POINT BEND TESTING

Influence of higher modes of vibration in the dynamic analysis of impa ct three point bend specimen based on Euler-Bernoulli and Timoshenko b eam theories are investigated in an attempt to predict the oscillatory behavior seen in the measured dynamic SIF history. Forced vibration o f the cracked beam is analyzed by normal mode summation method. Contac t force history computed using fundamental mode approximation is appli ed as input forcing function and the computed SIF histories are compar ed with finite element model and experimental data. Analytical and fin ite element results show that modes higher than the third have practic ally no influence on the notched beam response.