Flexural strength of recycled aggregate concrete reinforced with nylon fibers

The effect of binary blending of recycled aggregates and nylon fibers on the workability and flexural strength of concrete has been investigated in this work. An equal dosage of recycled aggregates from demolished wastes and conventional aggregates was used with 0.5 water cement ratio in preparing a mix of 1:2:4. Nylon fibers were used from 0% to 2% with an increment of 0.25% by weight of cement to reinforce the concrete. The slump cone test was determined for all nine batches of the concrete. Workability was observed to reduce with an increase in the content of nylon fibers. Flexural strength was evaluated by testing three prism specimens of 150mm x 150mm x 500mm size in each batch. A comparison of test results with control concrete (0% nylon fibers) and recycled aggregate concrete (with 50% recycled aggregates and without fibers) showed that nylon fibers helped in overcoming the loss of flexural strength due to the addition of recycled aggregates. The optimum dosage was recorded as equal to 1.5% with an increase in strength equal to 19.13% and 52.45% in comparison to conventional and recycled aggregate concrete.