ENPI Stone project
Evaluation of the durability of stone on constructions
The long term durability and the properties of natural stone used in the city environment have been studied. Material had been showing in different level visual weathering effects.
The research has been focusing on selected constructions for site evaluation, sampling and laboratory research. Visual inspections has been the first tool to assess the extension of weathering effects visible on site and has been performed with different tools benefitting also from new technologies as the use of Gigapan pictures.
In the research sampling technique using a minidrill has been developed and has been found to be adequate for sampling of 20mm diameter drill cores from massive construction elements.
Site tests had included Ground penetrating radar, Ultrasonic Pulse Velocity, Thermal camera, Schmidt Hammer, assessment of the biological colonization where biomaterial growth of a granite, including both field and laboratory analyses is researched as well as bacteriological research. Research on joint effect of biological and chemical weathering of natural stone, including also study on the atmospheric pollution and its effects on natural stone visible from the stone surface had been performed. Laboratory tests had included chemical analysis to evaluate chemical change of granite in crust and fresh sample calculating indexes of chemical weathering of granite. Moreover laboratory tests included natural rocks radioactivity, mineral structure and morphological features of city dust, distribution of organic chemistry on surface and in the deeper structure, petrographical analysis. Physical tests had been performed on the weathered and fresh material of available samples, defining water absorption, apparent density and porosity following EN standards as testing methods. The results were summarized partially in the publication “Evaluation of the Durability of granite in architectural monuments” where also the application of the method of qualimetrical expertise to assess the condition of a stone construction had been done and the coefficients of fractal dimension for different types of granites used to measure the degree of durability of breed had been calculated.
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GigaPan photography as a building inventory tool |
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Evaluation of the Durability of granite in architectural monuments |
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Site inspections from the Finnish sites had been collected in the report:AUTHORS: Finnish Geological Survey In the gallery are collected some images of the activity. |
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Non destructive analysis had been performed on the buildings sites also in cooperation with universities external of the consortium:
- Ultrapulse velocity: Polytechnic of Turin, Prof. Paola Marini. Measures performed with Dr. Claudio De Regibus and later on with Eleonora Castelletto (that has been producing a master thesis)
- Thermal camera: Mikkeli Univeristy of Applied Sciences. Summer work of Aleksei Shkurin.
- From Mikkeli UAS Daria Grishina has done a thesis on Microelement composition of rapakivi granite as an outside building material and the effect of air pollution on composition variation - Case of Saint Petersburg Bachelor’s Thesis Environmental Engineering
- By the Saint Petersburg State University: Sazonova Ekaterina, Mineralogical and geochemical features of granites weathering in the city environment of St.Petersburg
