| ■Tokyo National Research
Institute for Cultural Properties |
■Center for Conservation
Science |
| ■Department of Art Research,
Archives and Information Systems |
■Japan Center for
International Cooperation in Conservation |
| ■Department of Intangible
Cultural Heritage |
|
Survey scene at an old house
A vernacular house in which rammed earth and stone masonry structures coexist.
Since 2012, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been continuously engaged in research on vernacular houses in Bhutan, in collaboration with the Department of Culture and Dzongkha Development (DCDD), Ministry of Home Affairs, Royal Government of Bhutan. The DCDD promotes a policy of preserving and utilizing vernacular houses by integrating them into the legal protection framework of cultural heritage, while TOBUNKEN supports the initiative from academic and technical aspects.
Following the previous survey conducted in the eastern region from April to May 2023, the second field survey mission of this year was implemented from October 29 to November 4. Four staff members of TOBUNKEN, one from Nara National Research Institute for Cultural Properties (NABUNKEN), and two external experts were dispatched, and the team was joined by two staff members from DCDD. We jointly carried out a field survey in the two provinces of the central region, namely Bumthang and Wangdue Phodrang.
Most of the target houses had been identified in our preparative survey conducted in 2022. Eleven houses in total, including those newly found, were investigated this time in a detailed manner that included taking measurements and interviewing the residents. Two houses among them were rammed earth houses commonly seen in the western area of the country, and six were stone masonry houses widely located in the eastern area, while both construction techniques were combined in the other three houses. Especially in the eastern part of Wangdue Phodrang province, a tendency had been observed that the rammed earth technique was exclusively used further in the past, and stone masonry has gradually become dominant over time. However, our analysis of the transitional history of each house suggests that things were not so simple, and present more complex pictures.
On the other hand, although we had been focusing on such aspects as building type, construction technique, and transitional history of the houses, this time during the interviews we started to pay more attention to ethnographic factors such as oral traditions about houses and how each room is used. By adding information about villager’s lifestyles, which reflected on the transition and locality of the housing type, into our consideration, hopefully diverse values of the Bhutanese traditional houses as cultural heritage will become clarified.
The survey was implemented with the financial support of a JSPS Grant-in-aid for Scientific Research (B), “Vernacular stone masonry houses of Bhutan: study on the architectural characteristics and the suitable approach for protection as cultural heritage” with TOMODA Masahiko as the principal researcher.
Excavation of the Terrace on the West Embankment of the East Baray
The newly installed (left) and the existing (right) supports at hazardous spots inside the East Tower of the Central Complex
Ta Nei Temple is located facing the East Baray, one of the huge reservoirs that used to supply water for the Angkor capital. The terrace at the eastern end of Ta Nei Temple was built on top of the West Embankment of the East Baray, being not only significant as the main entrance of the temple, but also connected to the other temples through the Embankment. However, due to the extremely poor condition of the terrace, its construction period and structural features have remained uncertain.
The Tokyo National Research Institute for Cultural Properties has so far conducted excavation of the terrace in three periods: November 2017, March 2018, and August to October 2018, aiming to delineate the plan of the terrace and consider the intention of construction. These previous surveys revealed plans of the terrace, especially the structure of the west wing. In this term, four staff members were dispatched from November 5 to 30, 2023 to carry out archaeological and architectural studies to understand the northern and the southern sections of the terrace as well as the construction process, in cooperation with Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA).
Although traces of the stone masonry structure at the northern and southern sections of the terrace were scarcely identified, the excavation provided some clues to enable estimation of the original construction process of the terrace based on stratigraphical analysis of the mound structure. Additionally, a structure made of stones and bricks, which appears to be the foundation of a wooden pillar, was discovered on the surface of the terrace. Those remains indicate that a wooden structure was presumably built on the terrace at a certain time of its history. A level directly below where many roof tile fragments were unearthed by this excavation is thought to be the ground surface at the time when the wooden structure was built on the terrace. The details of the structure of the terrace still have not been ascertained, requiring further investigation.
In addition to the above-described investigation of the terrace, we conducted minor repair work on the East Gate that had been completed last year, and continued its documentation. Moreover, we installed additional supports at hazardous spots inside the East Tower of the Central Complex, and held on-site meetings to discuss future collaborative activities at the temple.
Remarks of His Majesty Preah Bat Samdech Preah Boromneath Norodom Sihamoni, King of Cambodia
Reporting on the conservation and sustainable development project of Ta Nei Temple
On November 15, 2023 Ms. KUROIWA Chihiro, Associate Fellow of the Japan Center for International Cooperation in Conservation, attended the “4th Intergovernmental Conference for the Safeguarding and the Development of Angkor” held at UNESCO Headquarters in Paris, France.
In 1992 following the end of the Cambodian Civil War, Angkor Monuments were inscribed on the World Heritage List, but at the same time, they were also placed on the List of World Heritage in Danger. At the first intergovernmental conference held in Tokyo in 1993, co-chaired by Japan and France and attended by 30 countries and 7 international organizations, the “Tokyo Declaration” was adopted calling for international cooperation towards safeguarding the monuments and sustainable development of the surrounding area. In the same year, the International Coordinating Committee for the Safeguarding and Development of the Historic Sites of Angkor (ICC-Angkor) was established to formulate technical guidelines and evaluate the activities of international conservation teams.
The Intergovernmental Conference takes place every 10 years to review and evaluate the ICC-Angkor and to discuss the policies for future conservation and sustainable development. The second conference was held in 2003 (France), the third in 2013 (Cambodia), and the fourth was held this time in Paris. In the past 30 years, numerous international projects for restoration and conservation have been implemented at the Angkor Monuments and Sambor Prei Kuk, another World Heritage Site.
His Majesty Preah Bat Samdech Preah Boromneath Norodom Sihamoni, King of Cambodia, H.E. Ms. Audrey Azoulay, Director General of UNESCO, H.E. Ms. Rima Abdul-Malak, Minister of Culture of the French Republic, Mr. KOMURA Masahiro, Parliamentary Vice-Minister for Foreign Affairs of Japan, and other international members attended the conference. During the technical session, presentations were made by teams from various countries involved in the conservation of Angkor and Sambor Prei Kuk monuments. We also reported on the collaboration with APSARA for the conservation and sustainable development of Ta Nei Temple.
Kheni village in Trashiyangtse province, composed of vernacular stone masonry houses
A house of typology unique to Merak district in Trashigang province
Measurement survey of a timber hut
Since 2012, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been continuously engaged in research on vernacular houses in Bhutan, in collaboration with the Department of Culture and Dzongkha Development (DCDD, formerly the Department of Culture, renamed recently upon restructuring), Ministry of Home Affairs, Royal Government of Bhutan. The DCDD promotes a policy of preserving and utilizing vernacular houses by integrating them into the legal protection framework of cultural heritage, while TOBUNKEN supports the initiative from academic and technical aspects.
Previously, our study focused on rammed earth houses commonly seen in the western area of the country. This year, we began a survey on stone masonry houses widely located in central and eastern areas, with the financial support of a JSPS Grant-in-aid for Scientific Research. The first survey mission under this scheme was implemented from April 25 to May 5, 2023.
Our group, comprising four dispatched staff members of TOBUNKEN and two from DCDD, jointly carried out a field survey in the five provinces spanning from Trashigang in the east to Bumthang in the central region. We observed stone masonry houses that appeared to have been built during earlier periods than other traditional houses in the target area, based on prior information collected by DCDD, and surveyed 14 houses in a detailed manner including taking measurements and interviewing the residents. Other than three cases of large-scale, three-storied residences of the ruling class, all were originally very small houses of one or two stories. In the Merak district of Trashigang, where a nomadic ethnic group lives, a unique typology of one-story houses without cattle sheds was widely observed.
Based on knowledge and information obtained during this survey mission, we plan to extend the target area and conduct more detailed investigations of the old houses we had already identified. In addition, since transition and locality of the housing type reflects change and difference of lifestyles, we feel a need to put more focus on these areas in the future. We will continue in our effort to further accelerate cooperation to prevent the loss of precious heritage against the trend that the numbers of vacant and degraded houses are increasing.
APSARA dance performed in the ceremony
Poster exhibition (TOBUNKEN poster is in the middle)
The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been working with the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) on the cooperation program for the Ta Nei Temple in the Angkor Archaeological site in Cambodia.
Angkor was inscribed on UNESCO’s World Heritage List in 1992. This led to comprehensive international support and cooperation from other countries, including Japan, which covers not only the conservation and restoration of the archaeological sites, but also various other fields like the formation of management systems, including human resource development, tourism development, and planning and infrastructure improvement for sustainable development of the surrounding regions. Angkor has been established as a top international tourist destination and became one of the most important sources of foreign currency revenue for the Cambodian economy. At the same time, it was highly praised as a successful model of international cooperation on the protection and utilization of World Heritage Sites, despite facing various challenges till date.
On the early morning of December 14th, 2022, I attended a ceremony commemorating the 30th anniversary of Angkor’s inscription on the World Heritage List. The solemn ceremony, held in front of the entrance causeway to the Angkor Wat Temple, started with Buddhist sutra chanting by many priests, where the APSARA dance was also performed. A poster exhibition on international cooperation history, including TOBUNKEN’s projects, was also held at the event.
On the following two days, the 36th Technical Session and the 29th Plenary Session of the International Coordinating Committee for the Safeguarding and Development of the Historic Sites of Angkor and Sambor Prei Kuk (ICC-Angkor) were held successively in Siem Reap City. For the previous two years, these regular meetings were held online due to the COVID-19 pandemic. This year, we finally managed to hold the meeting in person, with related experts and institute representatives both from and outside of Cambodia. The progress on many programs was reported and shared, and we revived the relationship among the related parties from various countries. I deeply appreciate the fact that in-person meetings as precious opportunities have finally resumed.
Arial view of Korphu village (from the west)
MoU signing ceremony (left: Director of the Japan Center for International Cooperation in Conservation, TOBUNKEN, TOMODA Masahiko; right: Director-General of the DoC, Nagtsho Dorji)
From the scientific research aspect, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) provides technical support for the value evaluation and enhancement of heritage buildings to the Department of Culture (DoC), the Ministry of Home and Cultural Affairs of Bhutan, which aims to expand the scope of heritage conservation to all historic buildings, including traditional houses. While we have been forced to implement cooperation projects online since January 2020 due to the worldwide COVID-19 pandemic, TOBUNKEN agreed with the DoC to resume joint surveys in Bhutan, following the significant easing of travel restrictions in Japan and Bhutan from July and September onward, respectively. From November 5th–15th, 2022, TOBUNKEN dispatched four staff experts, including an expert from the Nara National Research Institute for Cultural Properties.
The mission targeted the traditional masonry houses found in the eastern part of Bhutan. The purpose was to recognize and analyze the fundamental features of settlements and buildings in the region as the preliminary stage of the comprehensive scientific survey, which will serve as the basis for appropriate heritage conservation and development. Effective survey strategies were also examined in the mission. The on-site survey covered Trongsa Dzongkhag, Bumthang Dzongkhag, and the surrounding area, located in the central-eastern part of the country, which is relatively easy to access from the capital city of Thimphu. Measurements, photogrammetry, and interviews with locals were conducted in villages and houses preselected by the Division of Conservation of Heritage Sites (DCHS) of the DoC, based on the governmental archive and information provided by Dzongkhags. We found that the region had its own distinctive village forms. For instance, Trong and Korphu, located in the rugged mountainous area in the southern part of Trongsa Dzongkhag, are particularly unique as their houses are built in rows along a ridge, giving them merchant town-like appearance despite them being farming villages. In addition, while almost all houses in Trong are masonry structures, those in Korphu are both masonry and rammed earth structures, and rammed earth structures retain their older form. In other houses we surveyed, some were originally built in rammed earth, and later expanded or modified in stone. This suggests that, at least in the region surveyed this time, the structural manner of traditional houses shifted from rammed earth to masonry. We also found some masonry houses that have a very complex series of expansion and modification, and there is a possibility that the frequency of modification is generally higher in masonry structures than that in rammed-earth structures. Regarding the survey method, photogrammetry proved to be efficient and very useful in recording the masonry house, which shows random and complex patterns with natural stones and has many distortions in its shape.
After the on-site survey, a Memorandum of Understanding (MoU) for the cooperation in the conservation of architectural heritage was signed at the DoC headquarters, Thimphu, and a meeting was organized with the DCHS to discuss the results of the survey, as well as the prospects and needs of the Bhutanese counterparts. In the future, we expect to develop more on-site surveys and research activities targeting masonry houses in eastern Bhutan in close collaboration with the DCHS.
Symposium
Hanoi was previously called Thang Long and has been the capital of Vietnam most time since the establishment of the Lý dynasty – the first Vietnamese independent and unified nation at the beginning of the 11th century. The Imperial Citadel of Thang Long was where a group of imperial palaces, serving as both the emperor’s residences and the political control base, were located. The original palace remains were considered lost because the site was turned into an army facility in the modern age, while it was known that the palaces used to exist at the location.
However, the many remains, such as the foundations of the original palaces and related artifacts in each dynasty, including those from the Lý dynasty, were unearthed by a large-scale excavation investigation beginning in 2002, which was associated with the rebuilding of the Parliament House Building. This partially revealed how the Thang Long palaces used to be, although they were hidden for a long time. It was decided to conserve this site and it was inscribed on the World Heritage list in 2010, the 1,000th anniversary of the establishment of the capital. Responding to the request of the Vietnamese government, Japan has been cooperating in the research and conservation of this heritage since 2006. I had the responsibility of supporting architectural study and conservation management, as well as the overall implementation of this cooperation program from 2008 to 2013.
International Symposium: 20 Years of Research, Conservation and Promotion of the Values of Thang Long Imperial Citadel Heritage Site was held at the site co-sponsored by the Hanoi People’s Committee and UNESCO Ha Noi Office on September 8th and 9th, 2022, the 20th anniversary of the commencement of its investigation. Many representatives from governmental organizations, UNESCO, ICOMOS, and ICOM, and experts from and outside Vietnam participated and shared the research outcomes in each field. They also provided over 20 reports and conducted discussions regarding the challenges toward its future conservation and utilization. I made a presentation titled International Cooperation between Japan and Vietnam for the Conservation of Thang Long Imperial Citadel Site and also played the role of a commentator at a discussion.
Some have wished for some time now to reconstruct the Kính thiên palace, the main building, on the existing foundation of the later Lê dynasty (16th century or later). Several reports concerning the materials indicating reasonable grounds for the reconstruction were provided, and the study progress was stressed at this symposium. On the other hand, as the former military headquarters from the French Colonial period stand on this foundation and its front, it is necessary to demolish or relocate these buildings to reconstruct the palace. However, these buildings, founded later, are exactly parts of evidence indicating this heritage’s longevity and a layered record of vestiges identified as the World Heritage Outstanding Universal Value (OUV). Therefore, it is difficult to reconstruct the palace without OUV modification. Later, at the symposium, this topic was discussed in detail and it became the focus of discussion. After these in-depth discussions, the proposal of the Heritage Site Management Plan, including this reconstruction plan, was shelved, and the discussion summary to continue the discussion regarding the reconstruction of the Kính thiên palace was adopted.
While the cooperation program between Japan and Vietnam has been completed, I will closely monitor the conservation management movement of this heritage site.
Retouch work on the East Gate after restoration
Archeological investigation for digging a temporary ditch around the East Gate
Areas at risk on the East Tower Shrine of the central building complex: emergency replacement of reinforcements
The Tokyo National Research Institute for Cultural Properties (TOBUNKEN) continues to support the conservation and sustainable development project of Ta Nei Temple by the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) in Cambodia. We dispatched three expert members from June 12th to July 3rd, 2022. The mission aimed to supervise the finishing works for the restoration of the East Gate, conduct archaeological investigations for setting a new drainage ditch from around the East Gate, and survey the areas at risk of the central building complex.
For the East Gate restoration, in May, the APSARA team began retouching the parts identified at our previous dispatch in January 2022. We assessed their working status and further discussed how to deal with the broken part of stones and finish the surface with sculptures, and other aspects with APSARA. Although this resulted in additional work, we almost completed the given work by the end of June.
Furthermore, the water drainage around the East Gate had been an outstanding issue. In discussions with APSARA, it was decided to cut a temporary drainage ditch from the west side of the East Gate to the North Moat. We tasked Mr. KAHSHA Hiroo, a visiting researcher, with conducting archeological investigations related to a new drainage ditch set-up. We dug up a ditch carefully, to avoid damaging the original land surface at the time of constructing the East Gate and the Cruciform Terrace, and completed an approximately 30-meter-long temporary drainage ditch. We plan to carefully monitor its effect during the rainy season until October, in cooperation with on-site staff.
In the central building complex, we investigated the areas at risk in detail by scaffolding around the buildings of the Central Tower and the East Tower Shrines, which were identified as the highest priority for safety measures based on the discussions with the APSARA risk map team. Because the old wooden reinforcements in the areas at risk were severely deteriorated by pest damage and other factors, replacements using durable materials had been requested for some time. Following APSARA’s request, it was decided to tentatively replace the wooden reinforcements with scaffolding tubes and couplers. We renewed the reinforcements in a part of the Central Tower Shrine and three parts of the East Tower Shrine. We, in discussions with APSARA staff, tried to pursue minimum intervention while carefully examining lacking areas or cracks in the stone materials caused by imbalanced load transfers. Furthermore, safety measures were implemented by setting temporary fences along visitor routes to prevent tourists from entering the areas at risk.
We also held a working session with the Department of Tourism Development and Culture of APSARA as they planned biking tours around the area, including Ta Nei Temple. We exchanged ideas about the development of tourist facilities and discussed measures to protect the ruins, secure the visitors’ safety, and enhance visitors’ understanding of the ruins. We aim to further discuss effective ways to achieve balance between the appropriate protection and tourism for this site.
Onsite survey after the restoration of the East Gate
Survey for the risk parts of the central building complex
Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been engaged in technical cooperation for the conservation and sustainable development project of Ta Nei Temple by the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) in Cambodia. While it had been difficult to visit the site due to the COVID-19 pandemic, from January 9th to 24th, 2022, TOBUNKEN dispatched three staff experts responding to the request by APSARA for the first time after almost two years. We conducted the field survey and discussion on the points necessary for immediate consideration onsite including the East Gate under restoration as well as the parts of the central complex of the temple that are considered at risk.
The APSARA team have continued the restoration project of the East Gate started in 2019 by discussing the specific restoration direction online with us after April 2020. In January 2021, the reassembly work of the superstructure was completed up to the top. We checked the details onsite including the accuracies of the construction and the finishing details, which had not been well grasped remotely, and provided advice for improvement. Some retouching and additional works are planned based on the further discussion.
The central building complex of the temple requires immediate measures to secure visitors’ safety and prevent further damage to the ruins due to multiple risk factors including the collapse of unstable stone materials, aging of temporary timber reinforcements, and impacts by growing trees. Considering the given situation, we conducted a joint survey with the APSARA risk map team and discussed the main direction for countermeasures and the priority of temporary measures. We also recorded the current status of the towers by checking the upper part using a drone and creating 3D models from the photos taken.
In addition, the analysis of soil specimens taken in the previous archaeological survey at the front causeway was made with the assistance by Korea Cultural Heritage Foundation (KCHF), which also continues the restoration support in the Angkor archaeological site. In the APSARA Laboratory developed with Korea’s support, we conducted tests including grain size analysis and color measurement, which provided data related to the soil layer comprising the foundation of the causeway. We would like to express our gratitude to the generous support provided by KCHF.
We renewed our recognition of how important the onsite cooperative activities are, including interaction with the teams from different countries onsite and at research meetings. The mission also implemented the excavation survey of the outer enclosure and the survey on the stored sculptures from Ta Nei, which are reported separately.
The East Gate in the rainy season
The foundation of the outer enclosure and the land surface at Angkor Period unearthed
As part of the project mission from January 9th to 24th, 2022, we conducted an excavation survey of the outer enclosure remains of Ta Nei temple Under restoration of the East Gate implemented in cooperation with APSARA, the reassembly work has already been finished. However, due to the lower land surface than the surrounding area, it has been problematic in that the rain water accumulates around the gate in the rainy season. We assumed that this could hardly happen with the original setting when the temple was built, in which it was believed to have been equipped with some form of water drainage system. With this assumption, we conducted an excavation survey to understand the land surface level and terrain status at that time to plan a water drainage system around the East Gate area.
We conducted an excavation survey at the three points along the base remains of the wall that used to connect to the south and north sides of the gate (no information on the time and reason for removing the wall structure): its northeast corner and two locations where laterite blocks of the wall base are exposed up to the corner. The survey revealed that the land surface at these points in the Angkor period was about 30 centimeters below the current surface. This means that it was almost flat land without particular height difference from the surface around the East Gate. We did not find any remains such as drainage channels, so we consider that the drainage at that time depended on the natural drainage system including percolation.
The area to the north of the Gate is currently elevated, which prevents water evacuation. We will therefore remove the topsoil in that area and check if the rainwater can be discharged better. We plan to reorganize the surrounding area as well as the restoration of the temple buildings.
Damaged Dvarapala statue
Onsite survey
As part of the onsite survey mission from January 9th to 24th, 2022, the survey was conducted on the current location and status of the stone statues found in Ta Nei Temple and stored in other places. The French School of the Far East (L’Ecole française d’Extrême-Orient, EFEO) compiled the records of the discovery of the artifacts from different monument sites in Angkor. However, the systematic survey for the current status of these artifacts had not been conducted.
With the cooperation of the Angkor Conservation Office (ACO) under the Ministry of Culture and Fine Arts, we conducted a verification survey of the artifacts stored at that office against the records. There are a total of 30 plus artifacts from Ta Nei Temple on the inventory list created by the EFEO, among which, 16 items were identified at the storages of ACO this time. Most of the rest whose location remains unknown are small pieces such as hands or feet of divine statues. Among the massive statues of the gate guardian Dvarapala, which are about 2 meters high, three have lost their heads that were visible in the previous photographs. In addition, one of the Lokesvara (Avalokiteshvara Bodhisattva) statues was found to be heavily damaged. These damages are considered to be made by illegal diggings or destruction during the civil war period. The information from a French researcher onsite helped us to determine that at least two statues on the inventory, apart from the 16 items identified in the ACO, are currently stored in the National Museum of Cambodia in Phnom Penh.
We also found that a group of statues collected from the monument sites by ACO around in 1993 and 1994, when illegal diggings were most frequent, includes ones moved from Ta Nei Temple. We then identified seven Seated Buddha statues, seven Naga balustrades, and two Sinha statues. We will further investigate where they were originally located in the temple and where the rest of the artifacts are stored.
On the other hand, part of the head of a Lokesvara statue found inside the East Gate of Ta Nei during its dismantling in 2019 is stored in the Preah Norodom Sihanouk-Angkor Museum. We photographed it again for 3D model creation. The accompanying body parts have unfortunately not yet been found. It could still remain undiscovered on the site avoiding people’s eyes.
We plan to take the opportunity to conduct further surveys in the other facilities.
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.
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.
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.
Panel discussion at the third Mayors’ Forum
As part of the above-mentioned project commissioned by the Agency for Cultural Affairs, Tokyo National Research Institute for Cultural Properties (TNRICP) continues to support the building of an administrative network to conserve historic settlements in Nepal. On September 23rd and December 1st, 2019, workshops were organized in Kirtipur municipality with participation of engineers in charge of conservation of historic settlements from relevant municipalities. In response to their outcomes, “the third Mayors’ Forum on Conservation of Historic Settlements in Kathmandu and Kavre Valley” was held on January 5th, 2020, under the joint auspices of Kirtipur municipality and TNRICP.
The first Mayors’ Forum was held in 2018 in Panauti municipality for sharing the initiatives and issues related to preservation of historic settlements among the municipalities, followed by Lalitpur Metropolitan City in 2019.
Kirtipur municipality, whose old city area known as “a medieval settlement in Kirtipur” was listed as a UNESCO tentative list for World Heritage site, has been working on establishing its own rules for conservation. Therefore, the theme of this Forum was set as “regulatory framework for conservation of historic settlements,” and through two engineer workshops, the current issues pertaining to the systems were clarified and discussed while sharing information. As a result, the following were spotlighted as issues of administrative organizations and such systems: the existing framework for preservation of historic settlements is not effective since the policy for protection of cultural heritage of monumental nature is not linked with that for urban planning under national administration; some pioneering municipalities preserve their streetscapes under their original regulations, while others are formulating their regulations or criteria by focusing on completely different issues in municipal administration.
Accordingly, at the Forum, an officer in charge of national policy to protect cultural heritage and the one for urban planning reported about their respective conservation systems, and engineers from five municipalities delivered presentations on their legislation and issues to mutually share the tasks under national and municipal administration. Professor NISHIMURA Yukio of Kobe Design University gave a keynote speech titled “Effective Integration between Methods of Urban Planning and Preservation of Historic Settlements” while KANAI Ken, Head of the Conservation Design Section of the Institute, introduced some case studies on the Japanese system for important preservation districts of historic buildings. The Forum was attended by around 120 people, including State Minister of Urban Planning, five mayors and four deputy mayors, as well as engineers and researchers, who proactively exchanged opinions at the end.
Each municipality has several issues on conservation of historic settlements due to lack of financial and human resources, without sufficient support from the national government. Another reason for the ineffective functioning of the existing systems is insufficient basic research on historic settlements or lack of cooperative systems involving researchers and experts.
Consideration to lay the foundation to operate the network for conservation of historic settlements involving research institutions has just begun. It is anticipated that the autonomous and continuous cooperation among the persons concerned is strengthened to achieve a better environment around the historic settlements as well as its preservation.
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.
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.
Examining utilization strategies with local experts
Yuwakha village in Punakha, one of the surveyed settlements
Since 2012, Tokyo National Research Institute for Cultural Properties (TNRICP) has been conducting joint architectural research on rammed earth buildings in Bhutan with the Division for Conservation of Heritage Sites (DCHS), Department of Culture, Ministry of Home and Cultural Affairs, the Royal Government of Bhutan. From this fiscal year, TNRICP has started the Networking Core Centers for International Cooperation in the Conservation of Cultural Heritage Project, which was commissioned by the Agency for Cultural Affairs, with the objective of providing technical support and capacity building for the conservation and utilization of historic buildings in Bhutan. As a part of this project, a team of 11 experts, including TNRICP staff and outside experts, conducted on-site fieldwork from 20th to 28th August, 2019.
The field survey was jointly conducted with DCHS staff and covered traditional houses in the dzongkhags (districts) of Thimphu, Punakha, and Haa. The three main objectives were establishing a methodology for their conservation and repair, studying alternatives for their sustainable utilization, and clarifying the criteria for their evaluation as cultural heritage. Regarding the methodology for conservation and utilization, three traditional houses, which had been previously identified on the basis of features that indicated an early construction date, were selected as case studies. The potential methodologies for the seismic retrofitting of their rammed earth walls and the repair of their wooden members were studied. Furthermore, their potential use, compatible both with the owner’s demands and with the conservation of their value as cultural heritage, was examined during a discussion that involved DCHS staff, local architects, and owners. Regarding the evaluation of traditional houses as cultural heritage, comprehensive surveys were conducted in several settlements, and a potential method for the classification of traditional houses as well as a set of criteria for their designation as cultural properties was studied.
In addition, a Memorandum of Understanding referring to this project was signed at the Department of Culture, and a meeting was organized with the DCHS to discuss the results of this survey as well as the future prospects and needs of the Bhutanese counterparts.
In the future, we expect to continue cooperating with Bhutanese experts through on-site surveys and workshops to establish a methodology for the conservation and utilization of historic buildings suited to the Bhutanese reality.
Classroom lecture at Tokyo National Research Institute for Cultural Properties
Tour of restoration conditions at the Shinmachi-Furumachi District in Kumamoto City
A civil war broke out in Syria eight years ago in March 2011, and it seems there is no end in sight. Apart from the human cost of war, the much precious cultural heritage was also lost.
The Japanese government and the United Nations Development Programme (UNDP) began providing cultural heritage aid to Syria in 2017. From February 2018, the Archaeological Institute of Kashihara, Nara Prefecture, in association with academic organizations such as the University of Tsukuba, Teikyo University, Waseda University, Chubu University, and the Ancient Orient Museum, has been accepting Syrian specialists and providing them training in the fields of archeology and restoration. Tokyo National Research Institute for Cultural Properties is also participating in this project.
Following training seminars on conservation and restoration of paper cultural properties held in May 2018, this year, two Syrian specialists were invited to undergo training in “Research Planning Methods to Restore Historical Cities and Buildings” conducted from July 24th to August 6th.
Many historical cities such as the ancient city of Aleppo were engulfed in war, and many historical buildings were devastated. In the first half of this year’s training, seven specialists gave classroom lectures on surveying damage to historical buildings and making emergency repairs, structural safety diagnosis method, documentation and database creation method, restoration plan creation method, and restoration and preservation system creation method. For the practical aspect that comprised the second half of the training, participants inspected the restoration status of historical buildings and townscapes devastated by the 2016 Kumamoto Earthquakes, including Kumamoto Castle, the Shinmachi-Furumachi District, Kumamoto University, and the Eto-yashiki (Eto estate), which is registered as an important cultural property.
The participants also heard stories told by the people in charge. They visited Preservation Districts for Groups of Traditional Buildings in Kyoto and Nara and saw examples of repairs and applications of historical Japanese buildings.
We would once again like to thank the specialists, related organizations, and personnel-in-charge for their support.
Tokyo National Research Institute for Cultural Properties plans to continue support activities for Syrian cultural heritage in the future.
Participants at the expert meeting
Case study of the utilization of traditional houses (Fukusumi)
Tokyo National Research Institute for Cultural Properties (TNRICP) provides the Royal Government of Bhutan with technical support and human resource development for heritage conservation and sustainable utilization of historic buildings, including traditional houses, under the scheme of International Cooperation Project for Cultural Heritage by the Agency for Cultural Affairs in Fiscal Year 2019. TNRICP invited two staff members of the Division for Conservation of Heritage Sites (DCHS) from June 23rd to 28th to Japan to hold the first expert meeting and a case study tour in western Japan.
At the meeting, Mr. Yeshi Samdrup of DCHS presented a report on the progress of the development of the legal system concerning cultural heritage, and Mr. Pema Wangchuk of DCHS made a presentation on the prospects for the protection of traditional houses and settlements. Participants shared the recent challenges and dilemmas concerning the protection of cultural heritage in Bhutan through their presentations and the subsequent discussion. The subject of the field survey scheduled for this August was also discussed, and the specific survey method has been almost fixed.
In the case study tour, we visited the Ozaki family residence (Yurihama, Tottori), which is undergoing conservation work, and the Open Air Museum of Old Farm Houses (Toyonaka, Osaka) where typical traditional houses from all over Japan have been collected to study basic concepts of the protection of traditional houses as cultural property in Japan. We also visited historic towns and villages where historic townscapes have been rehabilitated, namely Shikano (Tottori), Oyacho-Osugi, Sasayama, Fukusumi (all above, Hyogo), and Miyamacho-Kita (Kyoto), to spread knowledge about community involvement and heritage tourism where traditional houses can be utilized as accommodation. The invitees were particularly interested in the nongovernmental management of cultural heritage that should be treated under the new law in Bhutan, and there was a lively exchange of views and opinions with the local presenters at each site.
We would like to extend our deep appreciation to all the people involved in the tour for providing this opportunity.
