Damage detection in structural elements using frequency contour method

Health Monitoring of Structures is a technique that helps to detect damage at earlier stage before failure occurs by sensing systems. Numerous methods are available to detect the damages based on dynamic characteristics of structures. Frequency contour method is adopted to detect the damage because this method consumes less time, detect location and size of damage accurately. Numerical Modal Analysis was performed on cracked and healthy beams of steel with different support conditions of size 20mm×20mm and of length 300mm using ABAQUS. The first three natural frequencies were obtained as basic criterion for crack detection.3D graphs of the normalized frequency in terms of the crack depth and location are plotted using MATLAB to locate the crack. The intersection of these three contours gives crack location and crack depth. Prediction of damage using frequency contour method gives good result.