MSA  Vol.8 No.6 , June 2017
Evaluation of Preservation Effect by Aquo-Siloxane Method towards Water Permeation and Material Diffusion into Porous Rocks
Abstract: Various kinds of heritages, such as architectures, statues, grave posts and towers, are made by stone, and they are facing the crisis of weathering. Therefore, it is necessary to give appropriate treatments to keep them in good conditions. Kyushu Research Institute for Cultural Properties Inc. and Kumamoto University introduced a new method, Aquo-Siloxane Method, in order to protect the stone heritages. In this study, preservation effect by Aquo-Siloxane method towards water permeation and material diffusion was verified. Here one-dimensional permeation and diffusion tests were conducted, and the intrinsic permeability and diffusion coefficient of rock samples with and without Aquo-Siloxane treatments were evaluated. As rock samples, 3 types of sandstones and concrete were applied. It was found that the permeability decreased to less than 1/10 to 1/100 of without Aquo-Siloxane treatment, and that the effect gradually developed during more than one year. One-dimensional diffusion tests were also conducted, and the diffusion process in rock samples are visualized by X-ray CT scanner system. It was confirmed internal structures of samples are clearly visualized, and that the diffusion process was also visualized as X-ray CT images. In order to extract the necessary information due to diffusion, image subtraction method was applied to image data. Then, by comparing obtained CT image data and numerical solutions, diffusion coefficients of rock samples with and without Aquo-Siloxane treatments were evaluated. As a result, diffusion coefficients also became smaller by applying Aquo-Siloxane treatments. It is revealed that material movement due to diffusion was also efficiently suppressed by applying Aquo-Siloxane method. Finally, Aquo-Siloxane method was applied to a stone heritage. It was found that no more chippings and cracks were observed and that the heritage has been kept in good condition for at least four years.
Cite this paper: Sato, A. , Egashira, M. and Obata, M. (2017) Evaluation of Preservation Effect by Aquo-Siloxane Method towards Water Permeation and Material Diffusion into Porous Rocks. Materials Sciences and Applications, 8, 419-435. doi: 10.4236/msa.2017.86029.

[1]   Al-Omari, A., Beck, K., Brunetaud, X. and Al-Mukhtar, M. (2015) Weathering of Limestone on Al-Ziggurat Walls in the Ancient Al-Nimrud City (Iraq). Environmental Earth Sciences, 74, 609-620.

[2]   Maraveas, C. and Tasiouli, K. (2015) Assessment and Restoration of the First Greek Power Plant—Registered Monument of Industrial Heritage. Case Studies in Structural Engineering, 3, 1-10.

[3]   Torok, A., Szabo, B. and Laszlovszky, J. (2015) Weathering and Preservation of Building Stones and Other Materials: Stone Masonry Material of a Medieval Monastic Glass Production Centre, Pomaz (Hungary). Engineering Geology for Society and Territory—Volume 8: Preservation of Cultural Heritage, 8, 471-475.

[4]   Nishiyama, K.-I., Miyamoto, K. and Hasegawa, S. (2014) Evaluation of Weathering Grade of Teshima Stone Used in Lithic Cultural Heritage, Kagawa Prefecture, Japan. Natural Science Research, The University of Tokushima, 28, 45-53.

[5]   Carmona-Quiroga, P.M., Blanco-Varela, M.T. and Martinez-Ramirez, S. (2015) Freeze-Thaw and UV Resistance in Building Stone Coated with Two Permanent Anti-Graffiti Treatments. Engineering Geology for Society and Territory—Volume 8: Preservation of Cultural Heritage, 8, 531-534.

[6]   Ghobadi, M.H. and Torabi-Kaveh, M. (2014) Assessing the Potential for Deterioration of Limestones Forming Taq-e Bostan Monuments under Freeze-Thaw Weathering and Karst Development. Environmental Earth Sciences, 72, 5035-5047.

[7]   Schiavon, N., De Caro, T., Kiros, A., Caldeira, A.T., Parisi, I.E., Riccucci, C. and Gigante, G.E. (2013) A Multianalytical Approach to Investigate Stone Biodeterioration at a UNESCO World Heritage Site: The Volcanic Rock-Hewn Churches of Lalibela, Northern Ethiopia. Materials Science and Processing—Applied Physics A, 113, 843-854.

[8]   Roussel, E. and Andre, M.-F. (2013) Quantitative Assessment of Pre- and Post- Restoration Weathering Rates of Limestone Mayan Temples (Uxmal, Yucatan). Geografia Fisica e Dinamica Quaternaria, 36, 169-179.

[9]   Meiklejohn, K.I. (1997) The Role of Moisture in the Weathering of the Clarens Formation of the KwaZulu-Natal Drakensberg: Implications for the Preservation of Indigenous Rock Art. South African Geographical Journal, 79, 199-206.

[10]   Heinrichs, K. (2008) Diagnosis of Weathering Damage on Rock-Cut Monuments in Petra, Jordan. Environmental Geology, 56, 643-675.

[11]   Walker, R.A., Wilson, K., Lee, A.F., Woodford, J., Grassian, V.H., Baltrusaitis, J., Rubasinghege, G., Cibin, G. and Dent, A. (2012) Preservation of York Minster Historic Limestone by Hydrophobic Surface Coatings. Scientific Reports, 2, 880.

[12]   Bugani, S., Camaiti, M., Morselli, L., Van De Casteele, E. and Janssens, K. (2008) Investigating Morphological Changes in Treated vs. Untreated Stone Building Materials by X-Ray Micro-CT. Analytical and Bioanalytical Chemistry, 391, 1343-1350.

[13]   Sato, A., Kanayama, S., Obata, M. and Toyomi, A. (2012) Water Retention Characteristics of Aquo-Siloxabe Method Aimed for the Preservation of Stone Cultural Heritages. Journal of MMIJ, 129, 529-537.

[14]   Sato, A. and Ikeda, K. (2015) Visualization of Diffusion Phenomena in the Porous Media by Means of X-Ray CT. Canadian Geotechnical Journal, 52, 1448-1456.

[15]   Sato, A., Kataoka, M., Asaue, H. and Obara, Y. (2012) Applications of X-Ray CT Methods to the Analysis of Transitional Phenomena in Porous Media at X-Earth Center, Kumamoto University. Proceedings of the 2012 World Congress on Advances in Civil, Environmental, and Materials Research, Seoul, 26-29 August 2012, 221-228.

[16]   Sato, A., Yoshitake, H., Shiote, T. and Sasa, K. (2011) Development of the Confined Pressure Type of Multi-Purpose Rock Flow System and Its Application to the Evaluation of Permeability of Various Geomaterials. ISRM International Congress on Rock Mechanics-Harmonising Rock Engineering and the Environment, 1357-1360.

[17]   Khalid, A.A. and Reed, A.H. (2010) Advances in X-Ray Tomography for Geomaterials.

[18]   Cnudde, V. (2013) Dominique Bernard. Proceedings of 1st International Conference on Tomography of Materials and Structures.

[19]   Sato, A. (2013) Analysis of the Tracer Diffusion Phenomena through Cracks in the Porous Media by Means of X-Ray CT. Materials Sciences and Applications, 4, 18-31.

[20]   Sato, A. and Ikeda, K. (2014) μ-Focus CT Observation of Stored CO2 in Porous Media by the Histogram Subtraction Method. Rock Mechanics for Global Issues— Natural Disasters, Environment and Energy, Paper No. CCS-6.

[21]   Nakashima, Y. (2006) The Use of X-Ray CT to Measure Diffusion Coefficients of Heavy Ions in Water-Saturated Porous Media. Engineering Geology, 56, 11-17.

[22]   Polak, A. (2003) Chemical Diffusion between a Fracture and the Surrounding Matrix: Measurement by Computed Tomography and Modeling. Water Resources Research, 39, SBH 10-1.

[23]   Sato, A., Yonemura, H. and Sasa, K. (2010) Analysis of Advection and Diffusion Phenomena in Cracks and into Rock Matrix Parts of Porous Rock by X Rays CT Method. Journal of MMIJ, 126, 647-653.

[24]   Sato, A., Ikeda, K., Yatsunami, T., Tsuda, K., Fukumitsu, T. and Habu, K. (2016) Prevention Effect of Material Flow in the Porous Rocks by Aquo-Siloxane Method. Rock Mechanics & Rock Engineering: From the Past to the Future, 2, 847-852.