Proceedings pro034: Microbial Impact on Building Materials

The impact of microorganisms on building materials was recognised many years ago for stones, metals and soil minerals. However, it is only in the last 15 years that biodeterioration of other important construction materials has been studied.



The big challenge for researchers in this field is to collaborate with experts in different areas, since biodeterioration research requires a knowledge of not only the microbiological mechanisms affecting the structure but also the material itself.



The first aim of the RILEM Technical Committee 183-MIB was to encourage the collaboration of a group of experts working in different fields such as Microbiology, Civil Engineering, Science of Materials, Chemistry and Geology. The majority of people working on biodeterioration of building materials were seen to be microbiologists. They are very organised and form many associations. However, it is necessary that more Material and Civil Engineers join these groups in order to help biologists to consider the properties of the building materials when studying the biological processes involved in biodeterioration.



The first meeting organised by RILEM TC 183-MIB was the International RILEM Workshop Microbial Impact on Building Materials, held in São Paulo, Brazil, in 2000. This second meeting deals with four themes, which cover the TC 183-MIB aim: techniques employed, biodeterioration of concrete and mortars, biodeterioration of different building materials, and prevention and treatment of biodeterioration of building materials.



The papers presented cover the following materials and areas:



1) Concrete: microbiological cleaning techniques, restoration and conservation of surfaces, chemical and physical deterioration by Limnoperna fortunei, proposal of methods for characterisation of algal growth, and damage processes caused by bacteria in sewage;

2) Mortar: colonisation by isolated Cladosporium sphaerospermum fungus;

3) Historical monuments: microbial and atmospheric effects, comparison of the relative role of atmospheric and biological impacts;

4) Timber: origin of fungal degradation and basic procedures to minimise these problems;

5) Several materials: preferences of lichen species.