A peer reviewed article investigating concrete block failure in Donegal homes has been published today in the number one ranked journal internationally for Building and Construction, Cement and Concrete Research.
The groundbreaking study claims that the geological mineral ‘mica’ is not the primary reason why thousands of homes in Donegal are crumbling. Experts found that the mineral pyrrhotite present in the aggregate accounts for the phenomenon of concrete failure.
The research is the first internationally peer reviewed article that provides clear scientific evidence that suggests defective concrete blocks in Donegal are failing as a result of internal sulfate attack directly connected to the presence of highly unstable pyrrhotite and not the mica freeze-thaw process. The mica freeze-thaw theory was proposed by a government report published in 2017 and incorporated into the National Standards Authority of Ireland (NSAI) testing and remediation standard I.S.464.
The paper found that the sulfur content of affected aggregates from Donegal was considerably in excess of the limit value defined by the European standard for concrete aggregates.
The new article, titled “The “mica crisis” in Donegal, Ireland – a case of internal sulfate attack?” is published by Dr Andreas Leemann, Prof. Barbara Lothenbach, Dr Beat Münch of Empa’s Laboratory for Concrete & Asphalt, Switzerland, Professor Paul Dunlop, School of Geography and Environmental Sciences, Ulster University, UK and Thomas Campbell, T.A Group, Ireland.
Professor Paul Dunlop from Ulster University stated that “this new scientific evidence is important for Government officials and policymakers who are dealing with the defective concrete block crisis to ensure science-based solutions are at the heart of government solutions for affected homeowners.”
“Its publications is also timely for the NSAI who have been calling for rigorous, independently peer reviewed scientific data for their ongoing review of I.S. 465. In addition, it provides scientific information for the National Building Control and Market Surveillance Office who are tasked with market surveillance about the obvious risks for concrete failure when aggregates containing pyrrhotite are used and reinforces the need for robust surveillance of the extraction industry and concrete manufacturers.”
Cement and Concrete Research is the highest ranked international peer reviewed journal by Scimago SJR in the subject category: Building and Construction. To be published in this journal, the scientific study in Donegal went through the rigours of the international peer review process, and as such, the methodology, results and conclusions can be accepted as being of the highest international scientific standard.
The full article is available online at: https://www.sciencedirect.com/science/article/pii/S0008884623000613?via%3Dihub