Effect of Recycled Aggregate on Behavior of Tied and Spiral Reinforced Fibrous Circular Short Columns

Abstract

This study focuses on studying the behavior of fibrous circular short columns (tied and spirally reinforced) using recycled coarse aggregate (f'c, ft, Ec, and fr) by using recycled aggregates with comparison to normal aggregates with and without using steel fibers. For this purpose, ten (10) short columns were cast at five groups each of two circular columns(tied and spiral of 150 mm radius x 600mm height) with different percentages of recycled coarse aggregate (0%, 50%, and 100%) and different percentages of steel fiber (0%, 0.5% and 1%). The study showed that when adding the 50% normal aggregates with 50% recycled aggregates, decreases of (10%, 18%, 30% and 22%) for (compressive strength, splitting tensile strength, flexural strength and elasticity module), respectively were observed, and when replacing the 100% normal aggregates with 100% recycled aggregates, decreases of (30%, 35%, 58% and 63%) for (Compressive strength f'c, splitting tensile strength ft, flexural strength fr and elasticity module Ec), respectively were observed. The changes on the compressive strength of adding steel fibers to the RAC by a proportion of (0.5% and 1 %) resulted in a significant increase of about (14 % and 35 %), respectively.

Keywords

• short column
• recycled aggregate
• steel fiber
• spiral reinforcement