Effect of industrial by-products incorporated in composites on strength and leaching parameters due to microbiologically induced corrosion

摘要

The durability of cement-based materials is an increasingly important characteristic for civil engineering structures due to the growing demand for their long service life and minimal maintenance.Mortars and concrete with high acid resistance are required for the construction and the repair of sewer structures, in which biogenic sulphuric acid attack is the major degradation mechanism.Important progress has been achieved in this regard with hybrid binders and materials known as supplementary cementitious materials(blast furnace slag, silica fume, fly ash etc.).These mainly industrial wastes and by-products increase many important properties of concrete structures such as acid resistance, permeability, strength and many more.This study investigates the effect of industrial by-products such as blast furnace slag and fly ash on strength and leaching parameters of composites exposed to bacterial influence.The medium with bacteria A.thiooxidans was used for microbiologically induced corrosion and the experiments were conducted during the period of 9 months.The sample with 95 wt.% of slag was found more resistible in bacterial environment compared to the sample with hybrid binder.