Indian Journal of Science and Technology

Abstract

Objectives: This project investigates the performance of mineral based composite in fibre retrofit under saline water corrosion as well as its behaviour at high temperatures in comparison to epoxy bonder. Methods/Experimental Analysis: Three types Fibre Reinforced Polymer (FRP) materials were used in retrofitting standard cylindrical concrete specimens subjected to various damage levels prior to its retrofit. The specimens were wrapped using epoxy resin and Mineral Based Composite (MBC) bonders before they were tested for their mechanical properties under high temperature. Apart from that, the carbon fibre samples were placed in marine conditions in order to investigate the effect of corrosion. Findings: Carbon fibre proved to be the most efficient retrofit with mineral bonder under various levels of pre-existing damage followed by aramid and e-glass fibres. Further, the MBC mix proportions were varied to accommodate industrial by-products such as class F flyash and metakaolin. The ideal mix proportions was later determined after a series of compressive tests and the finalized ratio was used in FRP retrofits under high temperature (100o C) alongside offshore environmental conditions. Epoxy had detrimental effects and lost its bonding capacity under these conditions whereas mineral composite established itself as a superior bonder. Around 205% strength development was observed in the tensile behaviour of carbon fibre retrofit and 30% replacement of cement with flyash seemed to perform optimally. Under severe temperature and marine corrosion, MBC bonded CFRP retrofit proved to be most durable. Thus, the significance of rehabilitating damaged concrete structures can be carried out globally using mineral based FRP strengthening technique which is sustainable solution. Application: From all the findings, it can be suggested that mineral bonding admixture can be adopted as a potential replacement for harmful epoxy resin under increased deterioration levels.

Keywords: Epoxy, FRP Retrofit, Rehabilitation, Sustainability, Temperature, MBC