An Algorithm for Estimating Bridge Deflection from Accelerometer Measurements

We present an algorithm to estimate bridge deflection (i.e. vertical displacement) from a sampled, noisy acceleration signal. The acceleration signal is first modeled as the sum of exponentially damped sinusoidal components. The model for the acceleration signal is then twice integrated analytically to obtain the displacement. The performance of the algorithm is demonstrated using measured data taken from an accelerometer mounted on a bridge. The experimental setup utilized a laser Doppler vibrometer to measure the actual bridge displacement. The measured displacement confirms that the estimated displacement obtained from processing the acceleration data is correct.