Model crystallization of salts and their migration in opuka stone – the local historic building material of Prague Castle Area, Czech Republic

0575148 - ÚTAM 2024 RIV CH eng C - Konferenční příspěvek (zahraniční konf.)
Kozlovcev, Petr - Painter, E. C. - Kotková, Kristýna - Válek, Jan - Maříková-Kubková, Jana
Model crystallization of salts and their migration in opuka stone – the local historic building material of Prague Castle Area, Czech Republic.
Structural analysis of historical constructions. SAHC 2023. Vol. 1. Cham: Springer, 2024 - (Endo, Y.; Hanazato, T.), s. 553-567. RILEM Bookseries, 47. ISBN 978-3-031-39602-1. ISSN 2211-0844. E-ISSN 2211-0852.
[International conference on structural analysis of historical constructions. SAHC 2023 /13./. Kyoto (JP), 11.09.2023-15.09.2023]
Grant CEP: GA TA ČR(CZ) TL03000603
Institucionální podpora: RVO:68378297 ; RVO:67985912
Klíčová slova: salt crystallization and migration * historic building constructions * opuka stone * climate cycles * archaeological sites of Prague Castle
Obor OECD: Materials engineering; Archaeology (ARU-G)
https://doi.org/10.1007/978-3-031-39603-8_45

Processes associated with crystallization and salt migration in building materials are important factors contributing to material degradation and subsequent damage. Archaeological structures located in the area of Prague Castle, for which the presence of salts and frequent climatic fluctuations are typical, are particularly vulnerable to salt-related deterioration. As part of the monitoring and closer research of the archaeological excavations of Prague Castle, long-term measurements of temperature and humidity were carried out in locations across the site. This data collection provided information on the effect of climatic cycles, including temperature and relative humidity changes, in the building materials. It was confirmed that the local opuka stone is highly susceptible to salt contamination and damage. The climate fluctuations cause critical conditions for dissolution and subsequent crystallization thresholds of the salts are regularly exceeded. This confirmed the significant impact of these cyclic changes in this archaeological area. In conjunction with data obtained from measurements of climatic cycles and opuka stone properties from the Third Courtyard of Prague Castle, a laboratory-based experiment was designed. The aim was to observe the crystallization and migration of salt in specimens of opuka stone. Stone specimens were immersed in sodium sulphate solution and exposed to specific climatic conditions (20 ℃ and 80, 70, 50 and 40% RH) that led to salt crystallization. The behaviour of salt was also studied under conditions where water vapor passes through the specimens. This experiment enabled the determination of the risk of damage as a function of salt crystallization in the opuka stone.
Trvalý link: https://hdl.handle.net/11104/0345476