Development of recycled PET fiber and its application as concrete-reinforcing fiber

We describe a method that can be used to produce concrete-reinforcing PET fiber from used PET bottles. Using this method, the concrete and PET fibers are easily mixed at a fiber contents as high as 3%. The primary characteristic of the PET fiber is that it is easy to handle. The issue of concern in the development of PET fiber is its alkali resistance; however, we encountered no problems when using the fiber in normal concrete. The wetting tension of PET was found to be lower than that of PVA but higher than that of PP. No toxic gas was generated during a combustion test of the PET fiber. We describe two example applications: a gateway support at Hishikari Mine, Japan, and the pavement of bush roads.