Abstract
X-ray system has often been employed in order to survey the arrangement of steel-fiber in concrete. The arrangement of plastic fiber, however, cannot be sufficiently evaluated by X-ray system. This paper presents a discernment method of plastic-fiber in concrete, and proposes the evaluation method of orientation factor. Black light and image analysis are employed for obtaining the orientation factor of vinyl fiber. Furthermore, the arrangement of else plastic-fiber is evaluated by using an image of colored concrete with phenol phthalein. By using such evaluation method, this study investigated an orientation factor of plastic-fiber in concrete lining of model tunnel.
