Structural retrofitting of corroded fly ash based concrete beams with fibres to improve bending characteristics

摘要

Generally, it is known that concrete and its embedded steel reinforcement progressively deteriorate when exposed to aggressive environments, yet when this defect deepens it leaves the concrete structure in unserviceable state. Therefore, the current study aims to evaluate the bending characteristics of corroded fly ash based fibre retrofitted concrete beams. Thus, the study attempts to measure the corrosion inhibition characteristics of fibre retrofitted reinforced concrete beams. Aside beams produced with conventional materials, other beams were produced with fly ash fixed at 30% replacement of Ordinary Portland Cement. Beams were cured in water for up to 34 days before they were induced in simulated corrosive environment. Some corroded beams were retrofitted with basalt fibre and others with sisal fibre, before being subjected to bending test. Despite the evident deterioration resulting from corrosion, the results clearly indicated that the fibres provided additional strengths to the corroded beams, with basalt fibre producing better response to loading at about 18% capacity than control beam before failure. Basalt fibre has been found to enhance the structural bending capacity of corroded member.