CONCRETE CRACK SENSOR

PROBLEM TO BE SOLVED: To provide a concrete crack sensor which can be easily attached on a crack part and by which observation can be easily performed by any person from some distance even in periodic patrol inspection and the like by utilizing a whitening phenomenon of fiber-containing plastic.SOLUTION: A fiber-containing plastic plate 1 is formed by infiltrating sheet-like fibers 5 into a matrix resin 6. The fiber-containing plastic plate 1 is applied on concrete 2 by an adhesive 4 so as to straddle a crack 3 of the concrete 2 to detect the subsequent growth of the crack 3. The expansion of the concrete crack can be estimated on the basis of the area of a whitening portion enlarging according to the enlargement of the crack width.