Laboratory Test to Evaluate the Resistance of Cementitious Materials to Biodeterioration in Sewer Network Conditions

The biodeterioration of cementitious materials in sewer networks has become a major economic, ecological, and public health issue. Establishing suitable standardized test is essential if sustainable construction are to be developed qualified for sewerage environments. Since purely chemical tests proven not representative the actual deterioration phenomena real conditions, biological test–named Biogenic Acid Concrete (BAC) test–was at University Toulouse reproduce reactions involved process concrete sewers. consists trickling solution containing safe reduced sulfur source onto surface substrates previously covered with high diversity microbial consortium. In these sulfur-oxidizing metabolism naturally develops biofilm leads production biogenic sulfuric acid on material. representativeness terms mechanisms been validated previous studies. A wide range have exposed during half decade. On basis this large database expertise gained, purpose paper (i) propose simple robust performance criterion (standardized leached calcium as function sulfate produced by biofilm), (ii) demonstrate repeatability, reproducibility, discriminability method. only 3-month period, was able highlight differences performances common cement-based (CEM I, CEM III, V) special aluminate cement (CAC) binders different nature aggregates (natural silica synthetic aluminate). proposed indicator (relative calcium) allowed classified according their resistance attack conditions. repeatability confirmed using three specimens same material within experiment reproducibility results demonstrated standardizing reference from 5 campaigns. Furthermore, developing post-testing processing calculation methods constituted first step toward protocol.