EULER BEAM BENDING WAVE SOLUTION PREDICTIONS OF DYNAMIC STRAIN USING FREQUENCY-RESPONSE FUNCTIONS

A procedure has been developed to measure dynamic strain in a beam by the use of two accelerometers placed on the beam and frequency response functions between them which relate measured accelerations at different positions to the fixed reference acceleration position. The reference acceleration is then employed to give the acceleration at the other positions. The experimental data along with the complete bending wave solution for an Euler beam enables one to calculate all the terms of the bending wave solution by the use of a matrix inverse. The solution is then used to calculate the dynamic strain in the beam for a random force input. Predictions of strain by using the procedure are compared with experimental measurements of strain obtained by using strain gauges. These comparisons show that the procedure predicts measured strain well for most frequencies, and for the near field and far field regions of the clamped boundaries and the point of force application. (C) 1995 Academic Press Limited