The bending strength of prestressed concrete can significantly be improved by using chemically modified chopped jute fibre as secondary reinforcement. A process methodology to homogeneously disperse jute fibers in the concrete mix was developed using carboxylated styrene butadiene polymer latex coating on mercerized chopped jute fibres and tannin as water reducing admixture. Compared to the control mixes, the reinforced concrete yielded increases of about 22% for compressive strength and 33% for flexural strength. Jute fiber reinforced elec- tric poles yielded an increase of about 3.3% in transverse strength and 1.6 times more deflection than conventional electric poles. Compared to conventional railway sleepers, a significant strength improvement under center top (~23%) and rail seat-bottom cracking load (~24%) was achieved in sleepers made using jute fiber reinforced concrete. The plausible role of secondary fibre reinforcement in improving the mechanical properties of concrete is discussed.
Materials Science Center Indian Institute of Technology