Application of stereovision method to detect concrete surface crack

To meet the evaluation requirement of the crack width on a concrete structure surface, the three-dimensional mathematical model of stereovision measurement method is researched, a 3D coordinate recovering method of crack edge is proposed by projecting a crack edge curve onto a space plane, accordingly the crack width is evaluated by the minimal distance method and the crack image recognition algorithm. The inspection experiments are performed on three concrete beams with the stereovision measurement system integrated in paper, which is destroyed in static test, crack width curves of two inspection zone of each beam are obtained. Compared with the micro-detector, experimental results show that the crack width evaluation algorithm based on stereovision can accurately measure crack width, it is verified that the stereovision method is feasible and useful for detecting concrete surface crack width.