NIST Time|NIST Home|About NIST|Contact NIST

HomeAll Years:AuthorKeywordTitle2005-2010:AuthorKeywordTitle

Rubber Particles From Recycled Tires in Cementitious Composite Materials.


pdf icon Rubber Particles From Recycled Tires in Cementitious Composite Materials. (1930 K)
Huynh, H.; Raghavan, D.; Ferraris, C. F.

NISTIR 5850 R; 23 p. May 1996.

Available from:

the authors

Keywords:

building technology; rubber concrete; rubberized mortar; plastic shrinkage; fibrous rubber; strength; recycled rubber tires

Abstract:

A possible method for recycling used automobile and truck tires could be to comminute them and incorporate the rubber particles into concrete. In a preliminary investigation, mechanical properties of mortar containing ground or shredded tires were evaluated. In this study, two different shapes of rubber particles were used as constituents of mortar : granules of about 2 mm diameter and shreds having two sizes which were, nominally, 5.5 mm x 1.2 mm and 10.8 mm x 1.8 mm (length x diameter). It was found that addition of rubber granules led to a decrease in both compressive and flexural strengths of mortar. On the other hand, the addition of rubber shreds improved some of the properties of the mortar. In particular, the crack width and crack length due to plastic shrinkage were reduced for mortar containing the 10.8 x 1.8 mm rubber shreds compared with a control mortar without rubber particles. The mortar containing rubber shreds showed workability comparable to that of a mortar without rubber particles. A mortar containing 25.4 mm long and 15 mm diameter polypropylene fibers showed poor workability compared with a mortar containing rubber fibers. Although further studies are necessary, it appears that the incorporation of shredded rubber could be beneficial for reducing plastic shrinkage crack development of mortar and probably concrete.