Salt weathering is a major concern for cultural heritages such as ruins and tombs, and desalination by poulticing is an interesting potential method to efficiently remove contaminating salt. Predicting the degree of achievable desalination is very important. However, many existing models used to consider saline water transport in porous materials have been developed based on the theory of pure water. To understand saline water flow in porous materials, we determined the saline water permeability of a tuff stone by the falling-head method. We found that the permeability of the tuff stone was affected by factors other than the density and dynamic viscosity of the saline water.

Over the past 10 years, our research team has holistically studied the environmental aspects of the conservation and restoration of the Hagia Sophia, which is suffering from severe degradation of its wall paintings, including the exfoliation of wall paintings and inner finishing materials, mainly due to salt crystallisation. In the present study, we investigated the influence of environmental factors and wall composition on the hygrothermal behaviour in the structure, such as moisture accumulation and evaporation within the walls, which significantly affect salt crystallisation. The differences in distribution of high moisture content at second cornice are depending on the azimuth, and the high correlation between high moisture content and deterioration severity is significant. A two-dimensional numerical model of the simultaneous transfer of heat and moisture considering the measured material physical properties and wall composition of the exedra wall is developed to quantitatively investigate the influence of environmental factors on moisture accumulation. Numerical results show that infiltrated rainwater tends to accumulate because the original builders used connection mortar, which has a much larger moisture diffusivity than that of modern mortar, and the accumulated water at the bottom of the wall is difficult to drain owing to the shape of the wall. In the northwest exedra, the influence of wind-driven rain on water accumulation is similar to that of runoff rainwater from the upper roofs, which probably causes deterioration over a wide area. In addition, the effect of the deterioration suppression measure by the re-covering of the outer surfaces of the west wall in 2013 is verified, and an appropriate suppression measure against water permeation is examined using a numerical model.

type:Article identifier:埋蔵文化財ニュース、No.179、pp.1-58 identifier:http://repository.nabunken.go.jp/dspace/handle/11177/9400

Heart rate variability (HRV) is the temporal fluctuation of heart rate (HR) and has been often used in the study of autonomic nerve activity of a human body. In this study, we applied a non-contact mat sensor to measure the HRV of human examinees during sleep in order to avoid any restriction of human body movement that may affect the sleeping condition during the experiment. The obtained HR data from the mat sensor was transformed into LF/HF (the ratio of a low frequency factor to a high frequency factor of the power spectrum of the HR) as an indicator of HRV. Then correlation analysis was performed to identify the strength of the relation between environmental factor, the Vital signs including LF/HF, and results from OSA sleep inventory MA version. The most significant correlation was found between the body motion and OSA subjective feeling of sleep.

This paper presents environmental measurement and numerically quantifying influences of the heat and moisture behavior in the stone Buddha carved into a cliff in Motomachi, Oita City. The simulation results show as follows. The water content is always high deep inside the Buddha statue but is low at and near the surface, which will result in more salt precipitation and thenardite-mirabilite cycles near the surface than deep inside the stone. The surrounding environmental and geological condition lead to more salt precipitation in autumn to winter and dissolution of thenardite often occurs in winter to spring, particularly at the knee.

6th International Building Physics Conference, IBPC 2015Hagia Sophia in Istanbul has been suffering from severe degradation of the walls mainly due to salt crystallization. The objective of this research is to elucidate the degradation mechanism and propose a suitable method for preservation. From field surveys and numerical analyses of heat and moisture behaviour in the walls, it was found that high moisture—primarily due to the infiltrated rain water—generally leads to the degradation of the inner and outer walls. Moreover, it is highly possible that evaporation, mainly at the middle-layer mortar, causes salt crystallization and exfoliation of the inside stucco wall surfaces.

Hagia Sophia in Istanbul has been suffering from severe degradation of the outside and inside walls and the paintings on the inside wall surfaces mainly due to liquid water transport and salt crystallization. In order to elucidate the degradation mechanism and then propose a suitable method for preservation, we have conducted a long-term field survey of Hagia Sophia from 2010 until 2014 and numerical analyses of simultaneous heat and moisture transfer in the walls. It was found that high moisture content — primarily due to penetration and evaporation of rain water and partly due to consequent salt crystallization — generally leads to degradation of both inside and outside walls. It was observed that the moisture content of the north inside wall is higher than that of the south inside wall due to less solar radiation. Also, there are high possibilities that evaporation mainly at the middle-layer mortar caused salt crystallization and exfoliation of the inside stucco wall surfaces and that the exfoliation of the inside finishing material of the wall caused further subsequent exfoliation of the inner layers.

This paper reports on measurements of water sorption isotherm of AAC (Autoclaved Aerated Concrete), commonly called ALC (Autoclaved Light-weight Concrete) in Japan, that contains salt (sodium chloride or magnesium chloride) water with a concentration that is low to saturated with undissolved salt in the material. The definitions of important parameters of porous materials that contain salt are clearly described. Measurement results confirm significant impacts of salt on sorption isotherm particularly at high salt concentrations. The measured sorption isotherm is modeled with the existing model that considers vapor pressure depression and the density of salt water. It is shown that differences between the measurement and the model increase with an increase of the amount of undissolved salt. Therefore, a modified model of water sorption isotherm for materials that do not only contain salt water but also undissolved salt is proposed and discussed. The modified model shows better agreement with the measurement.

This study examined influential factors towards occupants' window opening/air conditioner using behavior in the different situations in daily life through internet questionnaires surveys which were carried out in Kansai region in the summer of 2013 during 3 separate periods: mid-summer, late-summer and autumn. Object families filled out questionnaires about behavior towards opening windows/using air conditioners in a living room and master bedroom in 6 situations in daily life. Also, they answered questionnaires about family characteristics, house building features, dwelling environment and regional situations. The results suggested that the factors and its influence towards occupants' behavior could differ from situations in daily life.

In order to propose measures for the future preservation of the interior of Hagia Sophia, it is necessary to clarify the causes of deterioration. In the present study,thermal imaging and moisture content distribution measurement were conducted during fieldsurvey in September 2012. Moisture transfer in the wall was analyzed by using the indoor and outdoor temperature and humidity measured in September 2010. In addition, the appropriate time to cover the outside wall in order to prevent evaporation of accumulatedwater at the inside surface of the wall was examined by numerical simulation. The main results obtained are as follows.1)From the measurement of moisture content, it was found that the wall in all directions of the second cornice has moisture content of more than 20%. Especially the northwest side of the indoor wall surface of the second cornice has the highest average moisture content.2)The location of water flow on the wall can be identified from thermal image survey. At the location of the water flow, there is large peeling of the mortar joint.3) Numerical simulation shows that moisture content of the inner wall surface rises because of the penetration of rainwater at the outer wall surface.4)Numerical simulation shows that appropriate time to cover the outer wall is summer because the moisture content in the wall then is lower than in the other seasons.

Three different calculation models for wind-driven rain (WDR) on buildings are compared for two case studies for which full-scale measurements are available. The models are the semi-empirical model in the ISO standard for WDR (ISO), the semi-empirical model by Straube and Burnett (SB) and the CFD model by Choi, extended by Blocken and Carmeliet. This paper builds further on two generic studies in which these models were compared based on model theory and based on their application for idealized building configurations and for constant wind and rain conditions. In the present study, the models are applied to calculate WDR on the facades of a low-rise test building and a monumental tower building for actual transient rain events. The spatial and temporal distributions of WDR at the windward facade are determined and the model results are compared with each other and with the full-scale measurements. The agreement between the CFD results and the measurements is on average 20-25%, whereas the ISO and SB models show large discrepancies at many facade positions, up to a factor 2-5. The identification of the reasons for the discrepancies is based on the previous generic studies and on the detailed information provided by the validated CFD simulations. The reasons include: (1) the ISO and SB models do not take into account the wind-blocking effect; (2) they do not model the variation of shelter by roof overhang as a function of the wind speed and; (3) they only provide information for a limited number of building geometries. In spite of these deficiencies, these models provide a strong basis for further development. The deficiencies can be addressed with CFD, and it is suggested that future research should focus on improving the semi-empirical models based on the detailed results of validated CFD simulations. (C) 2010 Elsevier Ltd. All rights reserved.

Henshoku-shiken test paper for indoor air has been used in Japan to evaluate the cleanness of indoor air for over thiry years in the field of conservation of museum objects. It includes four colorants with glycerol, and it changes its color when it absorbs air contaminants, making it easy to detect the presence of alkalic or acidic contaminants in the air. In the mid-2005, a new type of passive monitor for indoor air, Passive Indicator® was brought to market. It includes two kinds of indicators: one that can detect ammonia and another that can detect carbonic acids like formic acid and acetic acid. To know the correlation between the two methods, simultaneous survey was conducted at 79 places in 21 museums. In places where much ammonia was detected, Henshoku-shiken test paper showed a tendency to turn green, leading to a misunderstanding that there was more alkalic pollutants in the air at the test site. It was also noticed that Henshoku-shiken test paper which was exposed to a relatively clean air often changed its color during transportation because it absorbed many pollutants. Since Henshoku-shiken test paper did not provide much accuracy in a clean place, it was decided to adopt the Passive Indicator® for evaluating air quality in museums accurately.

本研究は、歴史的建造物である旧甲子園ホテルの外装材として用いられている2種類の凝灰岩（日華石・竜山石）を対象として、それぞれにみられる剥離や欠損といった状態の異なる劣化の要因を、材料分析・熱水分移動解析・フィールド調査により明らかにすることを目的としている。令和３年度（2年目）は、以下の項目について検討した。 微環境の調査：前年度に続き、日華石について冬季の表面温度の実測を行い、凍結の有無を確認した。また、前年度示した夜間放射の影響を抑える対策について検討した。 材料物性の収集と整理：日華石と竜山石について、乾燥状態および湿潤状態での圧縮強度、引張強度のデータを得た。日華石は竜山石に比べ、自然状態での圧縮強度が1/13、引張強度が1/3.5と、強度が低いことが示された。また、日華石では、湿潤した場合の圧縮強度が乾燥時に比べて高い結果となった。さらに、両石材について凍結融解促進試験を行い、凍結融解のサイクルと物性の変化について検討した。両石材とも、凍結試験を繰り返すごとに、細孔径分布が変化し相対的に大きな孔が増えることで、高含水率域の水分伝導率が大きくなることを明らかにした。 材料内の熱水分状態の把握：一昨年度に作成した解析プログラムを用いて、実測した環境条件下での石材の水分状態の変化について一次元の解析を行った。降雨時の環境下での解析から、両石材において特徴的な含水状態の違いが示され、劣化状況との対応が確認できた。また、石材の細孔径の違いが含水領域と凍結範囲に影響しており、同じ気象条件下においても日華石には凍結が生じ、竜山石には生じない状況を明らかにした。 今後は、劣化箇所の定量的な把握方法の検討、実環境を境界条件とした解析による石材内部の熱水分状態の変化の予測、劣化の再現、保存修復方法の検討、同様の事例の調査を進める予定である。

研究分担者 伊庭 千恵美 京都大学, 工学研究科, 准教授 (10462342) 安福 勝 近畿大学, 建築学部, 准教授 (20581739) 佐々木 淑美 東北芸術工科大学, 文化財保存修復研究センター, 研究員 (60637883) 石崎 武志 東北芸術工科大学, 文化財保存修復研究センター, 教授 (80212877) 脇谷 草一郎 独立行政法人国立文化財機構奈良文化財研究所, 埋蔵文化財センター, 主任研究員 (80416411) 水谷 悦子 独立行政法人国立文化財機構東京文化財研究所, 保存科学研究センター, 研究員 (90849796)

研究分担者 友田 正彦 東京文化財研究所, 文化遺産国際協力センター, 保存計画研究室長 (70392553) 竹内 泰 宮城大学, 事業構想学部, 准教授 (30553862) 脇田 祥尚 近畿大学, 建築学部, 教授 (40280119) 安福 勝 近畿大学, 建築学部, 講師 (20581739) 田代 亜紀子 奈良文化財研究所, 企画調整部国際遺跡研究室, アソシエイトフェロー (50443148) 連携研究者 佐藤 桂 東京文化財研究所, 文化遺産国際協力センター, アソシエイトフェロー (80454198)

研究分担者 鉾井 修一 京都大学, 工学研究科, 教授 (80111938) 安福 勝 近畿大学, 建築学部, 講師 (20581739)