Crack detection in reinforced concrete beam utilizing correlation of acceleration and displacement data

Abstract This study presents an alternative method of crack detection in reinforced concrete (RC) beam utilizing correlation of acceleration and displacement data to the distance from crack initiation point, for early crack detection which are otherwise labour intensive and time consuming. Samples of mini RC beams of grades 25 and 30 were subjected to 3-point Glexural test to induce crack at the middle. Accelerometers sensors were placed equidistant on both sides from the crack initiation point to capture acceleration and displacement data. This study used these sensors to explore the crack detection based on wave attenuation concept in earthquake events, whereby intensity of energy released by crack formation reduced with the increase in the distance travelled by the crack energy wave. From the study, it was proven that the crack wave acceleration attenuates with distance whereby crack equations as function of acceleration for grades 25 and 30 are x = −0.0117a + 2.1756 and x = −0.1216a + 3.1776. Comparatively, the deformation (displacement) of RC beam decreases as the distance from crack initiation point increase, whereby crack equations as function of displacement are x = 2.8752u + 16.1136 and x =0.8659u + 7.5518 for concrete grades 25 and 30 respectively.