Preliminary Survey of Cultural Property Restoration in the Republic of Türkiye

Wall paintings of Keslik Monastery

Wall paintings of the Ephesus ruins

　The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) conducted a preliminary survey to establish a joint research project related to the restoration of cultural properties in the Republic of Türkiye. This joint research project aimed to make sustainable improvements in the operational methods and techniques of conservation and restoration plans. These issues were raised through the “Human Resource Development Project toward the Improvement of the Conservation and Management System for Mural Paintings in the Republic of Türkiye,” conducted by TOBUNKEN from 2017 to 2019. In Türkiye, emergency treatment has been prioritized for cultural property conservation. However, the country recently started focusing on the development of conservation and restoration experts specializing in various materials.

　We visited several regions of Trabzon, Şanlıurfa, and Cappadocia and some cities including Selçuk, and discussed with local experts conservation status and methods for conservation and restoration of cultural heritage. At Keslik Monastery, a Christian monastery located in the southern part of Cappadocia, the wall paintings on the inner walls are covered with thick soot layers from candles used in liturgical services over 1,000 years. The restoration of these wall paintings to their original condition was desired from the perspectives of both their protection and their touristic value. At the Ephesus ancient Roman ruins, members of the Austrian Archaeological Institute, who have been excavating there for a long time, explained to us that it is necessary to revise the current inconsistent conservation and restoration methods and to conduct research for the sake of establishing a basic policy.

　Researchers from Ankara Hacı Bayram Veli University, who cooperated with us on the Human Resource Development Project previously mentioned, accompanied us on this survey. We will identify what challenges shall be tackled based on the survey outcomes and build an implementable joint research framework with each cooperating institute. We target the next fiscal year to start this joint research to lead to the further development of cultural heritage protection and conservation and restoration activities in the Republic of Türkiye.

Technical cooperation activities during the COVID-19 pandemic: Conservation and sustainable development of Ta Nei temple in Angkor, Cambodia

Study on the reinforcement measures for the foundation structure of the East Gate

The ICC Secretariat visited the restoration work site of the East Gate (courtesy of APSARA)

　Tokyo National Research Institute for Cultural Properties provides continuous technical support to the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) for the conservation and sustainable development of the ruins of Ta Nei Temple in Angkor, Cambodia. Last year, the restoration of the East Gate began under the Conservation and Sustainable Development Plan jointly developed by APSARA and the Institute. APSARA is responsible for securing the budget for materials and labors, as well as implementing the work. The Institute provides technical assistance on restoration methodologies and procedures, as well as cooperation in architectural and archaeological surveys before and during the work.
　The possibility of our visiting Cambodia has all but disappeared after March this year, due to the global travel bans implemented to fight the COVID-19 pandemic. However, we cannot suspend the restoration work for our convenience, given that COVID-19 has not spread widely in Cambodia and the Cambodian counterpart has been continued regular site duties. From April, we have been benefiting from the advantages of Information & Communication Technology (ICT), actively utilizing interactive networking services with smartphones, besides normal e-mail messaging, to grasp real-time conditions at the site and hold online meetings as needed.
　On the 21st of April, an online meeting was conducted with the East Gate restoration team of APSARA to share the result of the foundation’s geological testing during February and March and discuss restoration methods and structural reinforcement measures, based on the test result. Two of our collaborators, Professor KOSHIHARA Mikio (Structural Engineering) and Professor KUWANO Reiko (Geo-technical Engineering) from the Institute of Industrial Science, the University of Tokyo, joined the meeting. After an in-depth discussion from a scientific perspective, the participants finally agreed on a basic scheme for the restoration and reinforcement with an aim to balance heritage authenticity and structural safety. Under this basic scheme, online meetings were held in May and July to study about treating the foundation and superstructure, respectively. We had interactive discussions and shared ideas, plans, and other useful information, as well as the site’s latest condition, and decided that, at this stage, the concrete restoration/reinforcement method be considered the most appropriate one.
　The Technical Session of the International Coordinating Committee for the Safeguarding and Development of the Historic Site of Angkor (ICC), organized at APSARA headquarters in June every year, was also postponed, and only the site visit by the ICC co-chairs and the secretariat was done this year. APSARA and the Institute jointly made the progress report and work plan of the project, including the activities mentioned above, and submitted it to the ICC secretariat prior to their site visit. We also held an online meeting with Professor MASUI Masaya of Kyoto University Graduate School, a member of the Ad Hoc Expert Group of the ICC, who supervised and advised us on our recent issues and the project’s work plan and exchanged information about latest information concerning international cooperation on Angkor.
　In this way, we accidentally realized a potential of ICT in heritage conservation. Indeed, there is a natural limit to conservation efforts based on telecommunication and remote information sharing because the universal value of cultural heritage is in its object itself. We hope that the world returns to normal, after overcoming the COVID-19 pandemic, and the days of unrestricted international travel are back soon.

Field Activities for the Conservation and Sustainable Development of Ta Nei Temple in Angkor, Cambodia (Part IX)

Dismantlement of the base platform.

Core sampling.

　Tokyo National Research Institute for Cultural Properties (TNRICP) has been providing technical support to the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) for the conservation and sustainable development of Ta Nei Temple in Angkor, Cambodia. As a part of this project, TNRICP dispatched a total of four members, including an outside expert, to Cambodia between February 26 and March 18, 2020 for 3D documentation of the base structure and an investigation of the foundation’s strength of the East Gate under restoration.
　Directed by Associate Professor Dr. OISHI Takeshi, from the Institute of Industrial Science, the University of Tokyo, a 3D laser scanning survey was conducted between February 27 and 28, 2020 to accurately record the state of the base platform including that in the excavation pits at the external corners of it, which were revealed after the superstructure was dismantled. After that, it was originally planned to conduct a flat-plate loading test and uniaxial compression test of the laterite substrate material. However, because of the spread of COVID-19, the experts in charge were unable to join the mission and only a simple dynamic cone penetration test (DCPT) was performed at the site, which was also conducted in December 2019.
　DCPT was conducted at 11 points to check the bearing capacity of the soil infill inside the platform and the foundation layer at the outer edge of the platform. The outcomes of the test indicated that test points below the wall structure have generally larger values than that of the central area (under the pavement). Although the factors such as the difference in the climatic conditions at the time the tests were performed (wet and dry season) might affect the test results, the long-term structural weight causing the rammed earth beneath the walls to get compacted could have caused this distinction. It could be interpreted as the soil infill inside the platform has developed a certain degree of strength enough to support the upper weight of the structure at present. In addition to DCPT, a core sampling was also conducted with a hand auger to check the cross-sectional structure, including the lowest layer of the foundation.
　Further, indoor material tests were performed by Professor Dr. KUWANO Reiko and Assistant Professor Dr. OTSUBO Masahide, from the Institute of Industrial Science, the University of Tokyo. Three kinds of specimens (original laterite stone, new laterite stone used for replacing deteriorated parts, and lime mortar used for the level adjustment) were tested in the laboratory through uniaxial compression test, etc. The test results indicated that there was no significant difference in the strength of the old and new laterite materials.
　The recent global pandemic has also affected our international cooperation project severely due to the difficulty of reaching to the site yet still the request of completion of the project as scheduled. However, we are trying to adapt to this situation by trying to find a way to communicate remotely with the counterparts through effective utilization of online meeting tools and the digital data of the structure that we have created thus far.

Cultural Exchange Project for the Conservation and Utilization of Historic Buildings in Bhutan (Part III）

On-site confirmation before the workshop (overlooking Kabesa village)

Discussions on the workshop (DCHS conference room)

　From this Fiscal Year, Tokyo National Research Institute for Cultural Properties (TNRICP) has started an Exchange Project for International Cooperation in Cultural Heritage commissioned by the Agency for Cultural Affairs to provide technical support and capacity building for the preservation and utilization of historic buildings in Bhutan. In 16th January 2020, as part of this project, TNRICP dispatched a team of six experts including three outside experts to participate the Workshop on Conservation of Lham Pelzom house organized by the Division for Conservation of Heritage Sites (DCHS), Department of Culture, Ministry of Home and Culture Affairs.
　Lham Pelzom house, located in Kabesa near the capital of Thimphu, is considered to be one of the oldest surviving farmhouses in the country, and is the top candidate for designation as historic farmhouses under Bhutan’s first comprehensive basic law on cultural heritage (New Law) which the government aims to pass. On the other hand, the house has been vacant for a long time, and its deterioration has been remarkable recently. Consequently, the need for preliminary consensus among stakeholders, such as the government, owners and local communities, on the potential for preservation and utilization is growing. Given this awareness, DCHS invited house owners, representatives of local communities, government officials from the Ministry of Work and Human Settlements, and Tourism Council to the workshop, for sharing various views on the conservation of the Lham Pelzom house. TNRICP joined the workshop for giving advice from the theoretical and technical point of view regarding heritage conservation.
　In the first half of the workshop, from the standpoint of promoting heritage protection, TNRICP proposed conservation policies and restoration methods based on field research, and DCHS reported on how government support should be provided, including financial aspects. Contrary, from the standpoint of the bearer of actual preservation, house owners strongly requested the need to secure economic benefits through common adaptive use, and local communities emphasized the need for the active involvement of the government in preservation. However, they all understood and welcomed a high reputation as a cultural heritage in general. Subsequently, in the second half of the workshop, meaningful mutual discussions unfolded in the latter half of the workshop, based on opinions, aspirations, and grievances of each participant in the first half. Finally, participants agreed to promote the conservation of Lham Pelzom house as the following conditions.
　(1) ACCELERATE procedures for value valuation as cultural heritage, such as designation under the new law,
　(2) CLARIFY protection frameworks, including administrative support for restoration works and the house owner’s obligations to the preservation,
　(3) CONSIDER a proposal for utilization that is appropriate as a cultural heritage and takes into account the house owner’s demand.
　TNRICP will cooperate with DCHS and continue research activities and field surveys to realize the conservation of traditional farmhouses in Bhutan as cultural heritage.

Field Activities for the Conservation and Sustainable Development of Ta Nei Temple in Angkor, Cambodia (Part VIII)

A scene from the ICC meeting

Dynamic cone penetration testing

　Tokyo National Research Institute for Cultural Properties has been providing technical support to the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) for the conservation and sustainable development of the ruins of Ta Nei Temple in Angkor, Cambodia. TNRICP dispatched a total of six members including outside experts to Cambodia from December 1st to 21st, 2019 in order to report the progress of dismantling the East Gate of the temple at the meeting of the International Co-ordinating Committee for the Safeguarding and Development of the Historic Site of Angkor (ICC), and investigate causes of uneven subsidence at the basement and floor of the East Gate.
　At theICC meeting at the APSARA headquarters office on December 10th and 11th, we delivered a report in association with Mr. Sea Sophearun from APSARA. Approval was granted to proceed with the conservation work further while utilizing the results of the dismantling survey, including a site visit by four specialized members of the committee. We also collected the latest information by exchanging opinions with persons in charge from APSARA, as well as experts within and outside Cambodia.
　To investigate the causes of uneven subsidence, we analyzed the old ground surface, and dug the southeast and northwest internal corners till the bottom of the stone foundation to check the condition of the East Gate base. This confirmed that the East Gate basement was made of roughly formed sandstone exterior, laterite groundwork, and internal landfill. It was also determined that the entire 　basement structure was built on a manmade soil layer using fine grains of sand. This sand layer seems to be the one that lends stability to the foundation on which the building was constructed. Similar techniques can been observed at other temple ruins in Angkor.
　After partially removing the floor pavement stone blocks, the bearing capacity of the foundation landfill was investigated with a dynamic cone penetration testing device in cooperation with Professor Dr. KUWANO Reiko from the Institute of Industrial Science, the University of Tokyo. The testing disclosed that the fragility of laterite used as base layer of the floor pavement and the strength of foundation landfill differed by location. This could be one of the causes of uneven subsidence.
　Based on the outcomes of this survey, we will examine how to improve the basement structure to ensure complete restoration of the East Gate.

Seminar III on Environmental Management at Museums for Iranian Researchers

Lecture at Tokyo National Research Institute for Cultural Properties

Lecture at the National Museum of Ethnology

　In March 2017, Tokyo National Research Institute for Cultural Properties exchanged a letter of intent with the Iranian Cultural Heritage, Handicrafts and Tourism Organization (ICHHTO) and the Research Institute of Cultural Heritage and Tourism (RICHT) to offer its cooperation in various academic fields for the protection of Iranian cultural heritage over the next five years.
　During the survey to explore the partner country’s needs conducted in Iran in October 2016, Iranian experts consulted us about the serious air pollution in the capital city of Tehran that resulted in damage to cultural properties. They said that even metal products displayed and housed in the National Museum of Iran might be eroding. Based on this information, we have been conducting seminars regarding the improvement of display and housing environment at Iranian museums since 2017.
　In 2019, we invited four researchers, two from RICHT and two from the National Museum of Iran, to Japan for a seminar from November 25th to 29th.
　First, lectures on museum environments were delivered at the Institute and were mostly led by SANO Chie, Director, Center for Conservation Science, and Dr. RO Toshitami, in addition to the presentation of a report on the results of air pollution monitoring conducted at the National Museum of Iran in 2018. The lectures on pest control for cultural properties were mostly led by SATO Yoshinori, Head, Biological Science Section, and Associate Fellow KOMINE Yukio.
　After the academic program, we visited the Kyoto National Museum and the National Museum of Ethnology. At the Kyoto National Museum, Dr. FURIHATA Junko delivered a lecture on disaster prevention measures before observing the disaster prevention system. At the National Museum of Ethnology, Dr. HIDAKA Shingo, Ms. WADAKA Tomomi, Ms. KAWAMURA Yukako, and Ms. HASHIMOTO Sachi conducted lectures on environmental management, air conditioning, pest control measures, and so on, while taking a tour of the exhibition halls and storage area. Once again, we express our gratitude to all the people and the institutes that have cooperated to support the program.
　The Institute will continue to offer its cooperation in various fields for the protection of Iranian cultural heritage.

Field Activities for the Conservation and Sustainable Development of Ta Nei Temple in Angkor, Cambodia (Part VII)

Dismantling work with a crane truck

Head of a statue found inside the East Gate

　Tokyo National Research Institute for Cultural Properties provides technical support to the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) for the conservation and sustainable development of the ruins of Ta Nei Temple in Angkor, Cambodia. During the period from September 7th to November 5th, 2019, the Institute dispatched a total of six members, including outside experts, to Angkor.
　In this restoration project of the East Gate of Ta Nei Temple, APSARA is responsible for implementing the dismantling work, while the Institute provides technical assistance, mainly on restoration methodologies, in addition to cooperation indocumentation and other scientific surveys .
　The team began dismantling the roof of the gate by using a crane truck after praying for the safety of all persons involved in the work at the ground-breaking ceremony on September 12th. The numbered stone blocks were removed one by one from the top during which each block was measured, photographed, and assessed with its damage condition.
　After dismantling the roof part, the tree roots and anthills invading the structure were removed, and the collapsed stones inside the building were taken out. Most of the collected stones, almost 70 in total,were revealed to fell down from the roof or pediment. They seemed to collapse naturally due to aging. Beneath the collapsed stones, broken head (measuring approximately 56 cm in height) of a statue, which could be identified as Lokesvara, was found leaning against the western wall of the south wing. This statue must be significant in that it is expected to shed light on the history of Ta Nei Temple, much of which is still unknown. After the find was documented with photography and 3D scanning to be described, it was moved to store at a APSARA’s facility for further study.
　In cooperation with the OISHI Laboratory at the Institute of Industrial Science, the University of Tokyo, the walls and the interior of the gate were documented with a 3D laser scanner, while the Structure from Motion (SfM) technique was used to record the walls in conjunction with surveying the structure in detail. Dismantlement of the walls started on October 16th and ended safely on November 5th with the completion of the required recording.
　A series of surveys following the dismantlement process disclosed the fact that the structure was deformed, partly because of the invasion of tree roots and anthills into the stone joints. Uneven subcidence of the foundation and floor surface suggests that the base structure might have some defects. The recovery of structural soundness requires the improvement of the base structure after clarifying the deterioration mechanism. Therefore, we will dispatch the staff again in December to excavate part of the foundation and investigate the ground.
　Besides, we attended the meeting of the International Coordination Committee for the Safeguarding and the Development of Preah Vihear Temple (ICC-Preah Vihear) at the APSARA headquarters office on September 18th to collect the latest information. While exchanging opinions with and collecting information from international experts, we will try to find the most appropriate way to conserve the Angkor ruins in cooperation with APSARA.