A Study of the Effects of Silage Effluent on Concrete: Part 1, Significance of Concrete Characteristics

This paper outlines an experimental facility that was used to study the effects of silage effluent on concrete by simulating the front of a 200 t horizontal silo. An effluent flow rate of 1431 of effluent per m² concrete per d and a flow period of 28 d were used to cause the corrosion associated with each year of service. Nine simulated years were studied and the effects on some durability related properties of concrete were assessed. The concrete mix variables studied were the effects of water and cement contents, water-reducing admixtures, pozzolanic admixtures, and the type of coarse aggregate. Only the surface of the concrete was affected by the effluent and it corroded at a rate of about 1 mm per simulated year. The importance of a low water/cement ratio in producing durable concrete was shown. Water-reducing admixtures and pozzolanas showed potential for reducing the deterioration of farm silos. The type of coarse aggregate was important in controlling the surface roughness.