Microbial acidification by N, S, Fe and Mn oxidation as a key mechanism for deterioration of subsea tunnel sprayed concrete
Journal article, 2024

The deterioration of fibre-reinforced sprayed concrete was studied in the Oslofjord subsea tunnel (Norway). At sites with intrusion of saline groundwater resulting in biofilm growth, the concrete exhibited significant concrete deterioration and steel fibre corrosion. Using amplicon sequencing and shotgun metagenomics, the microbial taxa and surveyed potential microbial mechanisms of concrete degradation at two sites over five years were identified. The concrete beneath the biofilm was investigated with polarised light microscopy, scanning electron microscopy and X-ray diffraction. The oxic environment in the tunnel favoured aerobic oxidation processes in nitrogen, sulfur and metal biogeochemical cycling as evidenced by large abundances of metagenome-assembled genomes (MAGs) with potential for oxidation of nitrogen, sulfur, manganese and iron, observed mild acidification of the concrete, and the presence of manganese- and iron oxides. These results suggest that autotrophic microbial populations involved in the cycling of several elements contributed to the corrosion of steel fibres and acidification causing concrete deterioration.

Amplicon sequencing

Biodeterioration

Biofilm community

Fibre-reinforced sprayed concrete; subsea tunnels

Metagenomics

Author

Sabina Karacic

Medizinischen Fakultät der Universität Bonn

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Carolina Suarez

Sweden Water Research

Lunds tekniska högskola

Per Hagelia

Norwegian Public Roads Administration (NPRA)

Müller-Sars Biological Station

Frank Persson

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Oskar Modin

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Paula Dalcin Martins

University of Amsterdam

University of Groningen

Britt-Marie Wilen

Chalmers, Architecture and Civil Engineering, Water Environment Technology

Scientific Reports

2045-2322 (ISSN) 20452322 (eISSN)

Vol. 14 1 22742

Subject Categories

Microbiology

Geochemistry

DOI

10.1038/s41598-024-73911-w

PubMed

39349736

Related datasets

DOI: 10.5281/zenodo.10406297

More information

Latest update

12/16/2024