Accelerated biodeterioration of various cementitious materials through an accelerated laboratory chamber

Author(s): Jean Herisson, Dominique Guinot and François Saucier
Paper category: Proceedings
Book title: Proceedings of the Final Conference of RILEM 253-MCI Microorganisms-Cementitious Materials Interactions Volume I
Editor(s): Alexandra Bertron and Henk Jonkers
ISBN: 978-2-35158-207-7 (Set)
ISBN: 978-2-35158-209-1 (Volume1)
e-ISBN: 978-2-35158-206-0
Publisher: RILEM Publications SARL
Publication year: 2018
Pages: 33-43
Total Pages: 288
Language : English

Abstract: Biodeterioration of cementitious materials in sewer network is a growing problem for sewer owners due to, among other things, the reduction of water consumption by the population or the separation of the network for rain and sceptic waters. The Fraunhofer UMSICHT has developed an accelerated test protocol allowing to reproduce - in a laboratory chamber - the H2S biogenic corrosion process found in sewers. This chamber allows to rank materials on a comparative durability scale. Five mortar formulations have been tested during 9 months in this chamber. As expected, materials based on ordinary Portland cement (OPC), used as a positive control, are less durable than those based on calcium aluminate cement (CAC). The use of a pore blocker in an OPC based formulation has shown a limited enhancement of durability. The geopolymer tested was less durable than the positive control. The use of reactive aggregates made of calcium aluminate in association with CAC, like in SewperCoat®, is the best solution in terms of durability.
Deterioration rates calculated from that work are of the same order as those obtained with the Hamburg chamber developed in the 1990’. As laboratory tests are performed in optimum conditions in terms of temperature and nutrients supply for the bacteria, they lead to deterioration rates which are much higher than those measured in real life.
This testing protocol permits to evaluate in laboratory, within 12 months, the potential durability of mortars over 25 years or more.

Online publication : 2018
Publication type : full_text
Public price (Euros) : 0.00