Sewer networks are subjected to many degradations including biodeterioration of materials in the presence of biogenic sulfuric acid, leading to costly rehabilitation. To ensure durable structures, it is necessary to select the most adapted materials. Two cementitious materials based on ordinary Portland cement (OPC) or Calcium Aluminate Cement (CAC), were submitted to biodeterioration in the headspace of an operating sewer network. After few months OPC materials start to deteriorate whereas CAC materials are still intact. The better durability of CAC materials is due to the presence of alumina providing a combination of protective mechanisms. On-site environmental parameters have been monitored and analysed in the context of the biological and chemical mechanisms involved in material degradation. These data will eventually feed the development of a representative, reproducible and accelerated laboratory test.
