Civil Engineering BINUS University

Fungi in Removing Cracks in Concrete

Concrete is one of the most important aspects of infrastructure.  In the manufacturing process, concrete requires special knowledge and techniques so that in result the strength will not only be appropriate but also long lasting. However, concrete can still be damaged due to various factors beyond human control such as extreme weather changes. Dry weather for example could make cracks occur on concrete. Cracks will also occur if the shrinking concrete is overloaded. When the concrete cracks were exposed to rain, the steel in the concrete will corrode over time and will reduce the strength of the concrete itself. Therefore, concrete maintenance must be carried out, though it is very costly and requires a lot of labour. The solution offered in this research is concrete that can heal its own cracks with the help of the Trichoderma reesei.  This research was inspired by the human body which can heal itself in the event of an injury.  Previously, there were 20 species of fungi tested in neutral to very alkaline environments, but only Trichoderma reesei survived.  The systematic use of this fungus is to include fungal spores, along with nutrients into the initial mix of concrete.  When cracks occur and air enters, mold spores that would not be active grow into a catalyst and will precipitate calcium carbonate crystals.  After all the cracks are closed (which stops air from entering), the fungus will return to the form of spores.  Trichoderma reesei is a fungus that is non-toxic to humans because it is environmentally friendly and non-pathogenic. In fact, this fungus is commonly used for wine fermentation which plays an important role in fermentation processes because it produces enzyme carbohydrase. This enzyme will be useful when there are cracks in concrete because the enzyme can react with CO2 in the air which will help the growth of a new matrix that will fill the cracks.  However, more research is needed on the use of fungi to treat cracks in concrete, because concrete is an extreme environment for mold growth (high temperature, high pH, small pore size, moisture deficit, etc).

Reference

Jin, Congrui. (2018, January 20). Fungi can help concrete heal it own cracks. Retrieved from https://theconversation.com/fungi-can-help-concrete-heal-its-own-cracks-90375