Title:
Field Assessment of Biogenic Acid Attack in Concrete Structures
Author(s):
Ali Abu-Yosef, Stalin Armijos-Moya, and Randall Poston
Publication:
Materials Journal
Volume:
120
Issue:
6
Appears on pages(s):
71-80
Keywords:
anaerobic digester; biogenic sulfuric acid attack (BSA); culture testing; microbiologically induced concrete corrosion (MICC); petrography; pH; quantitative polymerase chain reaction (qPCR)
DOI:
10.14359/51739147
Date:
12/1/2023
Abstract:
Biogenic sulfuric acid attack (BSA) is a biodegradation mechanism
that causes accelerated deterioration of concrete sewer systems
and wastewater treatment structures. BSA is a multi-stage biological
process that deposits sulfuric acid over concrete surfaces. Due
to its complex nature, there are no current standards to evaluate the
presence, extent, and severity of BSA in concrete structures during
service. The authors evaluated the chemical and biological conditions in an operational digester where BSA activity was suspected. The evaluation included microbial culture testing, quantitative polymerase chain reaction (qPCR) analysis of biofilm samples, pH measurements, and petrographic assessment of extracted samples. To evaluate the effect of oxygen on BSA activity, evaluations were performed in strictly anaerobic and oxygen-rich environments inside the same digester. The investigation determined that oxygen injection caused significant changes in the biological and chemical conditions inside the digester. The addition of oxygen promoted BSA activity and the associated production of sulfuric acid, and therefore accelerated concrete deterioration.