title: Evaluation of natural colonisation of cementitious materials: effect of bioreceptivity and environmental conditions.
abstract: Incorporation of living organisms, such as photosynthetic organisms, on the structure envelope has become a priority in the area of architecture and construction due to aesthetical, economic and ecological advantages. Important research efforts are made to achieve further improvements, such as for the development of cementitious materials with an enhanced bioreceptivity to stimulate biological growth. Previously, the study of the bioreceptivity of cementitious materials has been carried out mainly under laboratory conditions although field-scale experiments may present different results. This work aims at analysing the colonisation of cementitious materials with different levels of bioreceptivity by placing them in three different environmental conditions. Specimens did not present visual colonisation, which indicates that environmental conditions have a greater impact than intrinsic properties of the material at this stage. Therefore, it appears that in addition to an optimized bioreceptivity of the concrete (i.e., composition, porosity and roughness), extra measures are indispensable for a rapid development of biological growth on concrete surfaces. An analysis of the colonisation in terms of genus and quantity of the most representative microorganisms found on the specimens for each location was carried out and related to weather conditions, such as monthly average temperature and total precipitation, and air quality in terms of NOx, SO2, CO and O3. OPC-based specimens presented a higher colonisation regarding both biodiversity and quantity. However, results obtained in a previous experimental programme under laboratory conditions suggested a higher suitability of Magnesium Phosphate Cement-based (MPC-based) specimens for algal growth. Consequently, carefully considering the environment and the relationships between the different organisms present in an environment is vital for successfully using a cementitious material as a substrate for biological growth.
authors: Department of Construction Engineering, Universitat Politècnica de Catalunya, UPC, Jordi Girona 1-3, 08034 Barcelona, Spain; Magnel Laboratory for Concrete Research, Faculty of Engineering and Architecture, Ghent University, UGent, Technologiepark Zwijnaarde 904, 9052 Ghent, Belgium. Electronic address: sandra.manso@upc.edu.
authors: Sandra
authors: S
authors: Manso
authors: Department of Animals Health and Anatomy, Autonomous University of Barcelona, UAB, Building V, Campus of Bellaterra, 08193 Bellaterra, Spain.
authors: María Ángeles
authors: MÁ
authors: Calvo-Torras
authors: Magnel Laboratory for Concrete Research, Faculty of Engineering and Architecture, Ghent University, UGent, Technologiepark Zwijnaarde 904, 9052 Ghent, Belgium.
authors: Nele
authors: N
authors: De Belie
authors: Department of Construction Engineering, Universitat Politècnica de Catalunya, UPC, Jordi Girona 1-3, 08034 Barcelona, Spain.
authors: Ignacio
authors: I
authors: Segura
authors: Department of Construction Engineering, Universitat Politècnica de Catalunya, UPC, Jordi Girona 1-3, 08034 Barcelona, Spain.
authors: Antonio
authors: A
authors: Aguado
mesh_terms: D003252:Construction Materials; D004777:Environment; D004783:Environmental Microbiology; D016062:Porosity
keywords: Bioreceptivity; Cementitious materials; Intrinsic properties; Microorganisms; Natural colonisation