The use of recycled polymer fibers as secondary reinforcement in concrete structures.pdf

The use of recycled polymer fibers as secondary

reinforcement in concrete structures

Flynn L. Auchey

The Virginia Tech Polytechnic University

Blacksburg, Virginia

Abstract:

This paper presents the results of a feasibility study undertaken to identify the potential for using recycled high-density polyethylene (RHDPE) fiber as secondary reinforcement in Portland cement concrete structures.  This study demonstrated that: 1) It is feasible to use recycled high density polyethylene fibers as secondary reinforcement for temperature and shrinkage influences in Portland cement concrete structures, 2) RHDPE fibers appear to be able to be produced more economically than virgin polypropylene fibers, 3) RHDPE fibers appear to overcome several of the negatives presented by the virgin polypropylene fibers, including floating to the surface and impact on slump, and 4) Shrinkage crack propagation was controlled as effectively by the RHDPE fibers as by the virgin polypropylene fibers.  Four very important concerns relative to the use of RHDPE that were reserved for later study subject to the success of this study are: 1) the potential challenge of the alkaline reaction of the RHDPE material, 2) RHPD’s performance under extreme temperature cycling, water migration rate studies, 3) its performance under extreme temperature cycling, and 4) the impact of long-term plastic shrinkage.