Investigating the Effect of Sewage Corrosive Agents on Surface Corrosion and Porosity of Cement Concrete and Sulfur Concrete Structures

The corrosion phenomenon causes an enormous economic and ecological damage every year around the world. The purpose of this study was to conduct experiments to investigate and accurately determine the effect of sewage environment on the behaviour of sulphur and conventional concrete as the main material of sewage network structures. For evaluating the corrosion behaviour of concrete samples, porosity factor was measured. By analysing the SEM, EDX, EDS images, a non-dimensional index called Hole Index Ratio (HIR) was determined. It can be concluded that the main cause of the destruction of pipes made of cement concrete is chemical corrosion while sulphur concrete is more resistant in this case but has lower vulnerability to biological corrosion. It should be noted that under the real conditions and the presence of microbial competition between bacteria and the unfavourable conditions for the Thiobacillus thiooxidans bacteria, this malignant effect is far less and is negligible.