Effect of crevice morphology on SRB activity and steel corrosion under marine foulers

Localized corrosion of submerged steel H-piles was detected in a Florida bridge spanning over a brackish river. Analysis of the water showed proliferation of sulfate reducing bacteria (SRB). The steel piles had coincident heavy marine growth that may support biofilms and biocorrosion. The objective of the research described here was to identify the role of the physical morphologies of macrofouling on SRB activity and the aggravation of microbiologically influences corrosion (MIC) of submerged steel bridge. Laboratory experiments were carried out in nutrient-rich environments inoculated with SRB, with both porous and laminate crevice conditions characteristic of soft and hard marine fouling. It was confirmed that SRB proliferation can occur within the crevice environments, but aeration levels under crevices with interaction with the bulk solution can affect SRB activity. Electrochemical impedance spectroscopy pro-vided separation of environmental parameters and surface reaction parameters for the complicated sys-tems relating to corrosion under the porous and laminate crevice geometries. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study found that SRB can grow within crevice environments under both soft and hard marine fouling conditions, but aeration levels and interaction with the bulk solution at crevices may affect SRB activity. Electrochemical impedance spectroscopy provided insights into the complex systems related to corrosion under porous and laminate crevice geometries.