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Rafael Fort - One of the best experts on this subject based on the ideXlab platform.
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Artificial microcracking of granites subjected to Salt Crystallization aging test
Bulletin of Engineering Geology and the Environment, 2020Co-Authors: Ahmad Zalooli, Rafael Fort, Mohammad Reza Nikudel, Mashalah Khamehchiyan, David Martín Freire-lista, Shahram GhasemiAbstract:Salt Crystallization-induced decay of Vardavard granodiorite and Shirkouh monzogranite, two Iranian building stones, were assessed with two non-destructive methods: saturation-buoyancy technique and P- and S-wave velocity measurement. Moreover, polarized and fluorescence microscopy studies were used to evaluate the behavior of the studied stones at microscopic scale against a Salt Crystallization aging test. The aging test extended pre-existing microcracks and generated new ones. Intracrystalline microcracking was the most predominant microcrack type for both samples. Fine-grained Vardavard granodiorite experienced higher intercrystalline microcracking than coarse-grained Shirkouh monzogranite. The microcracking mechanism of feldspars substantially depends on their alteration degree and microstructural precursors. When a growing microcrack reaches a biotite, it propagates within the crystal if the growing microcrack coincides with the cleavage plane; otherwise, it propagates as an intercrystalline one. The increase in maximum microcrack length of the samples was higher than the increase in their mean microcrack length. Low-strength Vardavard granodiorite showed higher microcrack width after the aging test. Dry weight loss in low-strength Vardavard granodiorite was more pronounced than in high-strength Shirkouh monzogranite. Dry unit weight decreased at a higher rate than saturated unit weight with the increase of effective porosity. The reduction in ultrasonic wave velocities and the increment in effective porosity and water absorption were more pronounced for Vardavard granodiorite, indicating a higher degree of decay, i.e., higher microcrack generation, enlargement, and widening. Shirkouh monzogranite, which has large-sized crystals and pores, wider initial microcracks, high tensile strength, and low effective porosity and microcrack density, was more durable than Vardavard granodiorite.
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Corrigendum to “Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on Salt Crystallization decay” [J. Eur. Ceram. Soc. 33 (2013) 2031–2042]
Journal of the European Ceramic Society, 2014Co-Authors: Paula López-arce, Ainara Zornoza-indart, L. S. Gomez-villalba, Elena Mercedes Pérez-monserrat, Mónica Álvarez De Buergo, Gustavo Vivar, Rafael FortAbstract:Corrigendum orrigendum to “Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on Salt Crystallization decay” [J. Eur. Ceram. Soc. 33 (2013) 2031–2042] Paula Lopez-Arce a,∗, Ainara Zornoza-Indart a, Luz Gomez-Villalba a, Elena Mercedes Perez-Monserrat a, Monica Alvarez de Buergo a, Gustavo Vivar b, Rafael Fort a a Instituto de Geociencias IGEO (CSIC,UCM), C/Jose Antonio Novais 2, 28040 Madrid, Spain b Centre d’Arqueologia Subaquatica of Catalunya, Pedret, 95, 17007 Girona, Spain Available online 4 November 2013
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Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on Salt Crystallization decay
Journal of the European Ceramic Society, 2013Co-Authors: Paula López-arce, Ainara Zornoza-indart, L. S. Gomez-villalba, Elena Mercedes Pérez-monserrat, Mónica Álvarez De Buergo, Gustavo Vivar, Rafael FortAbstract:Non-desalinated and desalinated fragments of Iberian, Italic and Tarraconensian amphorae sherds, found in different underwater marine environments, were compared to determine the decay caused by Salt Crystallization. Polarizing light and fluorescence optical microscopy, scanning electron microscopy coupled to energy dispersive X-ray spectroscopy, X-ray diffraction, ion chromatography and mercury intrusion porosimetry tests were conducted on the samples. Non-desalinated samples exhibit a variety of signs of degradation, especially those samples fired at lower temperature. Sherds fired at higher temperatures have a lower surface area and less connected porosity, which entail a lower absorption of soluble Salts containing water and eventually less decay than those fired at lower temperatures. The composition and texture reached with the firing temperature is a key factor on Salt Crystallization decay and hence on the durability of these artefacts. This should be taken into account during desalination procedures that have to be optimized in order to be successful.
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artificial weathering of spanish granites subjected to Salt Crystallization tests surface roughness quantification
Catena, 2010Co-Authors: Paula Lopezarce, M J Varasmuriel, B Fernandezrevuelta, Alvarez M De Buergo, Rafael Fort, Cecilia PerezsobaAbstract:For hundreds of years, two types of granite (Zarzalejo and Alpedrete) from the Madrid region, Spain, have been extensively used as building stones. Fresh specimens of both stone types have been sampled from their respective quarries and subjected to sodium sulphate Salt Crystallization test (SCT). The resulting physical and chemical weathering patterns have been characterized by polarized light optical and environmental scanning electron microscopy. Water absorption under vacuum conditions and mercury intrusion porosimetry techniques were used to determine the pre- and post-SCT porosity and pore size distribution. The following non-destructive techniques were performed to assess stone durability and decay: ultrasound velocity (US) and surface roughness determination (SR) of intra- and inter-granular quartz, feldspar and biotite minerals at the centre as well as at the corners and edges of specimen surfaces. Before the SCT, US values were lower and SR values higher in Zarzalejo (ZAR) than Alpedrete (ALP) granite. After SCT, the US values declined while SR rose in both types of granites, with greater average differences in ZAR than ALP for both parameters. Feldspar and biotite and their inter-granular contacts were found to be the weakest and therefore the most decay-prone areas of the stone. The initial SR parameters were generally higher and rose more steeply after SCT at the corners and around the edges of the specimens. While behaviour was found to be similar in the two types of granite, variations were greater in ZAR, the less durable and more decay-prone of the two. Surface roughness measurement of mineral grains in granite stones is a very useful, in situ, non-destructive technique for quantifying Salt Crystallization-mediated physical and chemical weathering. The resulting quantification of decay and of related durability provides insight into the future behaviour of this type of stone, commonly used in historic buildings.
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PORE SIZE DISTRIBUTION AND THE DURABILITY OF A POROUS LIMESTONE
Quarterly Journal of Engineering Geology and Hydrogeology, 1997Co-Authors: Salvador Ordóñez, Rafael Fort, M. A. García Del CuraAbstract:Abstract A comparison of durability estimations based on mercury porosimeter data and experimental Salt Crystallization tests carried out on Bateig Stone from Alicante, Spain, establish that the main factor in the Salt Crystallization durability test is the ‘ink bottle’ pore system, identified by the presence of residual mercury in large pores after porosity testing. In addition, the results suggest that the commonly used indirect durability tests may not be considered a scientific definition of building stone behaviour.
Hassan Mohseni - One of the best experts on this subject based on the ideXlab platform.
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assessment of the effects of freeze thaw and Salt Crystallization ageing tests on anahita temple stone kangavar west of iran
Geotechnical and Geological Engineering, 2017Co-Authors: M. Heidari, M Torabikaveh, Hassan MohseniAbstract:Building stone of Anahita Temple seriously suffers from weathering due to long term freezing-thawing and Salt Crystallization processes. This article investigates possible changes of physical and mechanical characteristics of this stone subjected to freeze–thaw and Salt Crystallization ageing tests. Fresh samples obtained from the Chelmaran quarry (the main quarry supplying for Anahita Temple stone) were tested under freeze–thaw and Salt Crystallization experiments. The freeze–thaw and sodium sulfate Salt Crystallization are suggested to be the most effective factors affecting in apparent deterioration of the stone in compare to the magnesium sulfate Salt Crystallization test. Significant decreases in mechanical properties of the stone were observed after freeze–thaw and Salt Crystallization tests. However, more mechanical losses were recorded after the Salt Crystallization cycles than the freeze–thaw cycles. This is probably due to Crystallization pressure of Salt crystals in compare to ice wedging force, which promoted more development of micro-fractures in the specimens. Probably, intrinsic factors of the stone such as frequent calcite veins and stylolites, are the main factors that control the durability of Anahita Temple stone. Preferential weakening along these features during freeze–thaw and Salt Crystallization cycles led to physical destruction and strength loss of the stone. Based on comparison between experimentally induced damages and field observations, reasonably freeze–thaw process is major factor in weathering of Anahita Temple stone. It should be noted that recorded 102 frozen days for the region imply high destruction potential of the stone during freeze–thaw cycles.
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Assessment of the Effects of Freeze–Thaw and Salt Crystallization Ageing Tests on Anahita Temple Stone, Kangavar, West of Iran
Geotechnical and Geological Engineering, 2016Co-Authors: M. Heidari, M. Torabi-kaveh, Hassan MohseniAbstract:Building stone of Anahita Temple seriously suffers from weathering due to long term freezing-thawing and Salt Crystallization processes. This article investigates possible changes of physical and mechanical characteristics of this stone subjected to freeze–thaw and Salt Crystallization ageing tests. Fresh samples obtained from the Chelmaran quarry (the main quarry supplying for Anahita Temple stone) were tested under freeze–thaw and Salt Crystallization experiments. The freeze–thaw and sodium sulfate Salt Crystallization are suggested to be the most effective factors affecting in apparent deterioration of the stone in compare to the magnesium sulfate Salt Crystallization test. Significant decreases in mechanical properties of the stone were observed after freeze–thaw and Salt Crystallization tests. However, more mechanical losses were recorded after the Salt Crystallization cycles than the freeze–thaw cycles. This is probably due to Crystallization pressure of Salt crystals in compare to ice wedging force, which promoted more development of micro-fractures in the specimens. Probably, intrinsic factors of the stone such as frequent calcite veins and stylolites, are the main factors that control the durability of Anahita Temple stone. Preferential weakening along these features during freeze–thaw and Salt Crystallization cycles led to physical destruction and strength loss of the stone. Based on comparison between experimentally induced damages and field observations, reasonably freeze–thaw process is major factor in weathering of Anahita Temple stone. It should be noted that recorded 102 frozen days for the region imply high destruction potential of the stone during freeze–thaw cycles.
M. Heidari - One of the best experts on this subject based on the ideXlab platform.
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assessment of the effects of freeze thaw and Salt Crystallization ageing tests on anahita temple stone kangavar west of iran
Geotechnical and Geological Engineering, 2017Co-Authors: M. Heidari, M Torabikaveh, Hassan MohseniAbstract:Building stone of Anahita Temple seriously suffers from weathering due to long term freezing-thawing and Salt Crystallization processes. This article investigates possible changes of physical and mechanical characteristics of this stone subjected to freeze–thaw and Salt Crystallization ageing tests. Fresh samples obtained from the Chelmaran quarry (the main quarry supplying for Anahita Temple stone) were tested under freeze–thaw and Salt Crystallization experiments. The freeze–thaw and sodium sulfate Salt Crystallization are suggested to be the most effective factors affecting in apparent deterioration of the stone in compare to the magnesium sulfate Salt Crystallization test. Significant decreases in mechanical properties of the stone were observed after freeze–thaw and Salt Crystallization tests. However, more mechanical losses were recorded after the Salt Crystallization cycles than the freeze–thaw cycles. This is probably due to Crystallization pressure of Salt crystals in compare to ice wedging force, which promoted more development of micro-fractures in the specimens. Probably, intrinsic factors of the stone such as frequent calcite veins and stylolites, are the main factors that control the durability of Anahita Temple stone. Preferential weakening along these features during freeze–thaw and Salt Crystallization cycles led to physical destruction and strength loss of the stone. Based on comparison between experimentally induced damages and field observations, reasonably freeze–thaw process is major factor in weathering of Anahita Temple stone. It should be noted that recorded 102 frozen days for the region imply high destruction potential of the stone during freeze–thaw cycles.
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Assessment of the Effects of Freeze–Thaw and Salt Crystallization Ageing Tests on Anahita Temple Stone, Kangavar, West of Iran
Geotechnical and Geological Engineering, 2016Co-Authors: M. Heidari, M. Torabi-kaveh, Hassan MohseniAbstract:Building stone of Anahita Temple seriously suffers from weathering due to long term freezing-thawing and Salt Crystallization processes. This article investigates possible changes of physical and mechanical characteristics of this stone subjected to freeze–thaw and Salt Crystallization ageing tests. Fresh samples obtained from the Chelmaran quarry (the main quarry supplying for Anahita Temple stone) were tested under freeze–thaw and Salt Crystallization experiments. The freeze–thaw and sodium sulfate Salt Crystallization are suggested to be the most effective factors affecting in apparent deterioration of the stone in compare to the magnesium sulfate Salt Crystallization test. Significant decreases in mechanical properties of the stone were observed after freeze–thaw and Salt Crystallization tests. However, more mechanical losses were recorded after the Salt Crystallization cycles than the freeze–thaw cycles. This is probably due to Crystallization pressure of Salt crystals in compare to ice wedging force, which promoted more development of micro-fractures in the specimens. Probably, intrinsic factors of the stone such as frequent calcite veins and stylolites, are the main factors that control the durability of Anahita Temple stone. Preferential weakening along these features during freeze–thaw and Salt Crystallization cycles led to physical destruction and strength loss of the stone. Based on comparison between experimentally induced damages and field observations, reasonably freeze–thaw process is major factor in weathering of Anahita Temple stone. It should be noted that recorded 102 frozen days for the region imply high destruction potential of the stone during freeze–thaw cycles.
Paula López-arce - One of the best experts on this subject based on the ideXlab platform.
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Corrigendum to “Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on Salt Crystallization decay” [J. Eur. Ceram. Soc. 33 (2013) 2031–2042]
Journal of the European Ceramic Society, 2014Co-Authors: Paula López-arce, Ainara Zornoza-indart, L. S. Gomez-villalba, Elena Mercedes Pérez-monserrat, Mónica Álvarez De Buergo, Gustavo Vivar, Rafael FortAbstract:Corrigendum orrigendum to “Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on Salt Crystallization decay” [J. Eur. Ceram. Soc. 33 (2013) 2031–2042] Paula Lopez-Arce a,∗, Ainara Zornoza-Indart a, Luz Gomez-Villalba a, Elena Mercedes Perez-Monserrat a, Monica Alvarez de Buergo a, Gustavo Vivar b, Rafael Fort a a Instituto de Geociencias IGEO (CSIC,UCM), C/Jose Antonio Novais 2, 28040 Madrid, Spain b Centre d’Arqueologia Subaquatica of Catalunya, Pedret, 95, 17007 Girona, Spain Available online 4 November 2013
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Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on Salt Crystallization decay
Journal of the European Ceramic Society, 2013Co-Authors: Paula López-arce, Ainara Zornoza-indart, L. S. Gomez-villalba, Elena Mercedes Pérez-monserrat, Mónica Álvarez De Buergo, Gustavo Vivar, Rafael FortAbstract:Non-desalinated and desalinated fragments of Iberian, Italic and Tarraconensian amphorae sherds, found in different underwater marine environments, were compared to determine the decay caused by Salt Crystallization. Polarizing light and fluorescence optical microscopy, scanning electron microscopy coupled to energy dispersive X-ray spectroscopy, X-ray diffraction, ion chromatography and mercury intrusion porosimetry tests were conducted on the samples. Non-desalinated samples exhibit a variety of signs of degradation, especially those samples fired at lower temperature. Sherds fired at higher temperatures have a lower surface area and less connected porosity, which entail a lower absorption of soluble Salts containing water and eventually less decay than those fired at lower temperatures. The composition and texture reached with the firing temperature is a key factor on Salt Crystallization decay and hence on the durability of these artefacts. This should be taken into account during desalination procedures that have to be optimized in order to be successful.
R. Babazadeh - One of the best experts on this subject based on the ideXlab platform.
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experimental studies on the effects of cyclic freezing thawing Salt Crystallization and thermal shock on the physical and mechanical characteristics of selected sandstones
Rock Mechanics and Rock Engineering, 2015Co-Authors: M. H. Ghobadi, R. BabazadehAbstract:Rocks are used in engineering works as monuments, building stones, and architectural covering stones. Their weathering behaviors and physical and mechanical properties are the most important factors controlling their suitability as building stones. The aim of this study is to evaluate the weathering behaviors of sandstones from the Qazvin area (western Iran). In total, nine sandstones (A, B, C, CG, S, S1, Min, Tr, and Sh) were analyzed. Accelerated weathering processes, namely freezing–thawing (F–T), Salt Crystallization (SC), heating–cooling (H–C), and heating–cooling–wetting (H–C–W), were used. Sandstones were subjected to 60 cycles of F–T, H–C, and H–C–W and 20 cycles of SC, and changes in characteristics including weight loss (%), P-wave velocity loss (%), and changes in uniaxial compressive strength (UCS) and point load strength were recorded after different numbers of cycles. The results from our laboratory studies indicate that rocks from the same stratigraphic layer can show major differences in weathering properties, and their sensitivity to these processes are different. Also, it was found that the thermal behavior of sandstones under wet and dry conditions were different. In the next stage of this study, a decay function model was used to statistically evaluate the disintegration rate. This model showed that the disintegration rate was higher for Salt reCrystallization compared with F–T, H–C, and H–C–W processes.
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An investigation on the effect of accelerated weathering on strength and durability of Tertiary sandstones (Qazvin province, Iran)
Environmental Earth Sciences, 2014Co-Authors: M. H. Ghobadi, R. BabazadehAbstract:Damages to stones induced by the action of freeze–thaw and Salt Crystallization are considered to be of great importance in engineering construction. These processes can influence the strength and durability of porous materials and consequently deteriorate them. In this study, the effects of freeze–thaw (F–T) and Salt Crystallization (S-C) phenomena on strength and durability of Upper Red Formation sandstones were investigated. Nine specimens of sandstones were collected from different parts of Qazvin area (Iran), and then their physical and mechanical characteristics were determined. To assess the effect of F–T and S-C on physical and mechanical characteristics of sandstones, 60 cycles of F–T test and 20 cycles of S-C test were performed. Physical and mechanical characteristics of these sandstones including wave velocity (Vp) changes, weight loss (%), point load index and Brazilian tensile strength were determined after different cycles. For assessing the effect of freeze–thaw and Salt Crystallization phenomena on slake durability index (SDI) of sandstones, slake durability test was performed on specimens subjected to F–T and S-C. Then changes occurred in the SDI after 15 cycles were investigated. Finally, the long-term durability of sandstones against freeze–thaw and Salt Crystallization action was evaluated using a decay function model. This model postulates a first-order process, and provides some meaningful parameters such as decay constant and half-life for the evaluation of long-term durability of stones. Based on results obtained from current study, it can be concluded that in comparison to freeze–thaw, Salt Crystallization can considerably reduce the strength and durability of sandstones. Also, parameters obtained from decay function model showed that the rate of integrity loss is different for different weathering processes, and stone durability can be predicted by this method with good accuracy.
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Experimental Studies on the Effects of Cyclic Freezing–Thawing, Salt Crystallization, and Thermal Shock on the Physical and Mechanical Characteristics of Selected Sandstones
Rock Mechanics and Rock Engineering, 2014Co-Authors: M. H. Ghobadi, R. BabazadehAbstract:Rocks are used in engineering works as monuments, building stones, and architectural covering stones. Their weathering behaviors and physical and mechanical properties are the most important factors controlling their suitability as building stones. The aim of this study is to evaluate the weathering behaviors of sandstones from the Qazvin area (western Iran). In total, nine sandstones (A, B, C, CG, S, S1, Min, Tr, and Sh) were analyzed. Accelerated weathering processes, namely freezing–thawing (F–T), Salt Crystallization (SC), heating–cooling (H–C), and heating–cooling–wetting (H–C–W), were used. Sandstones were subjected to 60 cycles of F–T, H–C, and H–C–W and 20 cycles of SC, and changes in characteristics including weight loss (%), P-wave velocity loss (%), and changes in uniaxial compressive strength (UCS) and point load strength were recorded after different numbers of cycles. The results from our laboratory studies indicate that rocks from the same stratigraphic layer can show major differences in weathering properties, and their sensitivity to these processes are different. Also, it was found that the thermal behavior of sandstones under wet and dry conditions were different. In the next stage of this study, a decay function model was used to statistically evaluate the disintegration rate. This model showed that the disintegration rate was higher for Salt reCrystallization compared with F–T, H–C, and H–C–W processes.
