Welcome to the event website of RILEM TC 253-MCI.

The RILEM TC 253-MCI warmly invites you to participate in the one day conference: 'Microorganisms-Cementitious Materials Interactions'

This event will take place on Thursday 23 June 2016 in Delft, The Netherlands.

This one-day conference will be open to all interested in both positive and negative (detrimental) interactions between microorganisms such as bacteria, fungi and micro algae and cement-based materials used for infrastructures and buildings. The one-day conference will be preceded next day (24 June) with the half-yearly Technical Committee meeting which is open to TC 253 members only.

Conference context:

Infrastructures and buildings are exposed to microorganisms in different ways: in many cases microorganisms have detrimental effects on structures and construction materials, however, in specific cases interactions can be beneficial. Structures exposed to aqueous media or general outdoors or indoors conditions are often also exposed to microorganisms.

Deleterious effects of microorganisms such as bacteria, fungi, and micro-algae on cementitious materials can be linked to the production of aggressive metabolites (acids, CO2, sulphur compounds, others), but also to specific physical and chemical effects that microorganisms also in form of biofilms impose on the surface of these materials. Alternatively, specific material properties such as porosity, roughness, mineralogical and chemical composition can influence the receptivity of the material for growth and proliferation of specific microorganisms.

Physical and aesthetic deterioration lead to significant repair costs of structures, andproduction of hazardous compounds by microorganisms may lead to health problems, specifically in the indoors environment.

However, on the other hand, specific microorganisms may also have beneficial effects on cementitious materials when their presence and metabolic activity can lead to protection or even self-repair of constructions. New formulations of cement-based materials, incorporating selected bacteria and suitable chemical precursors, are developed with the aim to form protective organic polymers (EPS=ExoPolymeric Substances) or to fill micro-cracks in concrete with bio-derived inorganic minerals, and thus improve durability properties.

More and more research efforts are devoted to these topics related to cementitious materials-microorganisms interactions within local or trans-regional initiatives. It is now necessary to implement concerted approaches and comparison of research outcomes to move toward a better understanding of the phenomena and furthermore to standardization and/or certification.

The four topics of the conference are in line with the subjects of the four TC 253-MCI working groups:

Topic 1: Deterioration of cement based materials by microorganisms in different contexts (waste water networks, agricultural plants, biogas systems, agrofood environments and others)

Topic 2: Proliferation of microorganisms (algae, fungi) on building materials in indoor conditions

Topic 3: Algae and fungi colonization on building materials and protection of materials

Topic 4: Engineered bacteria-based protective systems for cementitious materials

These topics will be introduced and current state-of-the-art discussed by specialists in these four fields, see detailed program below. Contributions in form of poster pitches and poster presentations on these subjects by conference participants are welcome.