Tests on workability and strength of high strength-flowable concrete containing PET waste fiber

Abstract

This study describes two workability tests, compressive strength and tensile strength tests of high strength flowable concrete containing plastic fiber prepared from polyethylene terephthalate (PET) waste bottles. For the high fluidity mix Vebe time and V-funnel time tests were carried out. Results show that there is a Vebe time increase with PET fiber addition to concrete being increased with increasing fiber volume and fiber length. V-funnel time was found to reduce when up to 0.75% fiber volume is added to concrete, followed by an increase for larger fiber volumes. When fiber length is increase, there is more time increase, but in general, V-funnel time increase was lower than that of Vebe time, indicating a different influence of PET fiber on the compatibility and flowability. The measured V-funnel time for all mixes was found to conform to the limits of European specifications on the flowability of self compacting concrete. Small descending in compressive strength was recorded for RPET fiber reinforced concrete that reached 15.74 % for 1.5 percent fiber content with 10 mm fiber length. Attractive results was recorded in split tensile strength of RPET fibrous samples which resulted in improvement up to 63.3 % for 1.5 percent of 40 mm fiber length content.