Deterioration of reinforced concrete in sewer environments

Abstract

Millions of dollars are being spent worldwide on the repair and maintenance of sewer systems and wastewater treatment plants. Microbially-induced corrosion causes damage via micro-organisms. Deterioration is caused by acid excretion which etches the surface of concrete, penetrating the mortar surface, especially in sewer systems. The mechanisms of concrete and reinforcement deterioration in sewer environments and microbially-induced corrosion is discussed in detail in this paper. A comprehensive review is given of the role of hydrogen sulphide and micro-organisms in the deterioration of concrete in sewer environments and of repair and rehabilitation measures, including the following preventative measures: (a) modification of the materials used in construction of sewer pipes; (b) coatings; (c) sewer treatments. A complete review of the microbial deterioration of concrete and its remedies is also included.