| ■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 |
|
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.
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.
Site visit by members of the Ad Hoc Experts Group of ICC
Removal of scattered stone blocks with the mobile crane
Tokyo National Research Institute for Cultural Properties (TNRICP) 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. TNRICP dispatched a total of five staff members to Cambodia from May 19th to June 29th, 2019 in order to carry out preparatory work before the examination of the restoration plan for the East Gate by the International Coordinating Committee (ICC) and the start of the restoration work.
APSARA and TNRICP submitted the plan for dismantling the structures to the ICC technical session, which was held on June 11th and 12th. As a result of careful deliberation including a site visit by the three members of the Ad Hoc Experts Group, the plan was adopted as proposed with minor corrections. As necessary preparation for the restoration work, we cleaned out and organized scattered stone blocks around the East Gate, and also carried out excavations for drainage route examination.
We recorded and numbered scattered stone blocks and moved them out of the way of the restoration work. Thanks to the mobile crane provided by Nara National Research Institute for Cultural Properties (NNRICP), which is restoring the Western Prasat Top Site, we were able to move the stone blocks in a short time.
During the excavation we tried to clarify the difference in the old ground surface level between the northeast end of the Cruciform Terrace and around the East Gate, in order to examine the natural drainage route from the East Gate area. The elevation around the East Gate is lower than the surrounding area, and it is feared that rainwater may stagnate there, which is why we plan to set up a drainage channel to the North Moat for future maintenance. In addition, we found laterite stone paving which is presumed to be a part of the approach that connects the Cruciform Terrace and the East Gate. It is expected that further excavations will provide clearer information.
A presentation during the seminar
Since 2017, Tokyo National Research Institute for Cultural Properties has held three seminars on the topic of wooden architecture in Southeast Asia. The first and second seminars were focused on clarifying the features of already lost ancient wooden buildings through archaeological data. The third seminar was held on December 16th, 2018 under the title “Wooden Architectural Techniques in Mainland Southeast Asia: Development and Mutual Influences”. This time, the objective was to analyze the features of existing buildings in order to deepen our understanding of wooden architectural techniques, their development, and the influences both inside and outside the region.
Mr. François Tainturier, from the Inya Institute of Myanmar Studies, made a presentation about Myanmar and Cambodia. Wooden architecture in both these countries is characterized by the use of a simple structural framework, with few horizontal members, supporting straight multi-tiered roofs. Especially in the case of Myanmar, roofs are profusely decorated with carvings.
Mr. Pongthorn Hiengkaew, from the Fine Arts Department, Ministry of Culture of Thailand, made a presentation about wooden buildings in Thailand. Although their features vary depending on region and period, as a common feature, horizontal members and struts are employed in order to create roofs with curved shapes.
Finally, questions from the audience were answered and a panel discussion was held with the participation of Mr. Shoichi OTA, from the Kyoto Institute of Technology, with the objective of laying the foundations for a history of wooden architecture in Southeast Asia beyond current national divisions.
The proceedings of this seminar will be published next fiscal year.
The on-site workshop in Bagan
Since the August 2016 Chauk Earthquake in Myanmar, Tokyo National Research Institute for Cultural Properties (TNRICP) has been carrying out research and survey activities directed at improving the quality of the conservation work of the damaged historic brick buildings in Bagan, as part of a cooperation project commissioned by the Agency for Cultural Affairs of the Japanese Government (recommissioned by the Nara National Research Institute for Cultural Properties, NNRICP). On November 13th and 14th, 2018, two workshops were held at the Myanmar Engineering Society (Yangon) and the Bagan Branch Office of the Department of Archaeology and National Museum (Ministry of Religious Affairs and Culture) respectively, to share the results of this project with local experts.
Members of TNRICP and Japanese experts were lecturers at the workshops and they focused on three main topics: traditional brick masonry techniques, structural features of brick buildings, and chemical analysis of traditional mortar. In addition, local experts from each partner institution made presentations on the current state of conservation and repair works of brick buildings in Bagan. The workshops concluded with a questions and answers session and an opinion exchange between Japanese and local experts.
The results of this project will be published in a report and shared with the local experts so that they can be applied further to conservation and restoration work.
In addition, the Third Technical Coordination Forum for Safeguarding Bagan and the First International Coordination Committee (ICC) was held in Bagan on November 17th and 18th, 2018. The objective of the meeting, chaired by the Minister of Religious Affairs and Culture, was to share information and coordinate efforts between different local and foreign expert teams carrying out conservation work at Bagan. Experts from TNRICP took part in the meeting and made a presentation on the currently ongoing cooperation projects by TNRICP and NNRICP.
Excavated terrace structure
Survey of the current condition of the temporary supports
The Tokyo National Research Institute for Cultural Properties has been carrying out technical cooperation with the Authority for the Protection and Management of Angkor and the Region of Siem Reap (APSARA) in order to draft a conservation and management plan for Ta Nei Temple in Cambodia. From November 28th through December 8th, 2017, we conducted an archaeological investigation and a risk assessment for the structures at Ta Nei Temple for the second time.
The main purpose of the archaeological investigation was identifying the remains of the east approach to the temple located at its front and the remains of a structure situated on the upper surface of the embankment of the East Baray reservoir discovered during the first investigation in July. The excavation was conducted jointly with staff from APSARA and with the cooperation of the Nara National Research Institute for Cultural Properties.
First, we set up and excavated a trench 2 m wide from east to west and 5 m long from north to south, approximately 50 m to the east of the east gate. We discovered a hardened surface, presumably the old approach to the temple, 70 cm beneath the current ground surface. The hardened surface was composed of yellow soil covering a layer of small sandstone gravel 5 mm in size overlapped on a layer of fist-sized sandstone cobbles.
In addition, we set up and excavated a trench 11 m long from east to west and 1 m wide from north to south on the embankment of the East Baray on the prolongation of this approach way. We found a laterite stone surface 30 cm beneath the current ground surface (Figure 1). Considering the surrounding topography and the distribution of exposed laterite, these remains can be presumed to form part of a terrace structure approximately 20 m long from east to west and 15 m wide from north to south.
Regarding the risk mapping of the site, we examined how to renew the existing temporary supports. Wooden supports had been installed in 16 places where there were safety concerns such as potential collapse of main structures, including the central tower, the east tower, and the inner gallery. However, apart from obstructing the view of the site, these supports are in need of renovation, as in the 20 years that have passed since their installation decay of timber members and loosening of joints have become apparent. Thus, we observed and recorded the current condition of these supports, and studied improvement proposals including a change to a more durable material and the adoption of a design enabling fine adjustment.
The General Assembly
The 19th ICOMOS General Assembly and Scientific Symposium was held in Delhi, India from 11th to 15th December. The author took part in the General Assembly and made a presentation at the Symposium.
During the General Assembly, the triennial elections for the Executive Committee were held. Professor Toshiyuki Kono from Kyushu University was elected as president, becoming the second Asian and first Japanese president of ICOMOS since its foundation in 1965. Professor Kono has had a leading role in several initiatives engaging current issues surrounding cultural heritage from multiple perspectives, including the Convention for the Safeguarding of the Intangible Cultural Heritage, the Nara+20 Conference and the ICOMOS Project on Cultural Heritage Recovery and Reconstruction. The further development of such initiatives during his three year term is highly anticipated.
In addition, the General Assembly officially adopted the “Principles for the Conservation of Wooden Built Heritage”, redacted by the ICOMOS International Wood Committee (IIWC). This document is an updated version of the 1999 charter by the same committee. The updated version is more detailed and concrete, while at the same time placing a renewed emphasis on the intangible aspects of wooden built heritage.
The General Assembly also saw the adoption as one of its resolutions of a proposal redacted by the Emerging Professionals Working Group, aimed at strengthening the involvement of emerging professionals in the activities of ICOMOS.
At the Scientific Symposium, under the title “Heritage and Democracy”, speakers from different countries presented initiatives aimed at involving actively in the conservation process the local communities and other stakeholders who maintain, use and safeguard the heritage. As an example of such initiatives in Japan, the author made a presentation on the “heritage manager” system.
Risk assessment
Trench excavation and the ditch revealed (created with SfM)
The Tokyo National Research Institute for Cultural Properties is providing technical support to the Authority for the Protection and Management of Angkor and the Region of Siem Reap (hereafter APSARA) to draft a plan for the conservation and management of Ta Nei Temple. From July 16 to 30, 2017, we carried out an archaeological excavation and risk assessment of the buildings (Figure 1).
Our excavation was mainly to identify remains of the East Approach to the temple, located at its front. We worked with APSARA staff with the cooperation of the Nara National Research Institute for Cultural Properties. When we cleared the underbrush along about 100 meters from the Eastern Gate of the outer enclosure to the East Baray reservoir, we discovered remains of a laterite terrace on the bank of the reservoir, suggesting the high likelihood of this location being the starting point for an approach leading to the Eastern Gate.
We first opened a trench measuring 2 meters east-west and 10 meters north-south about 12 meters east of the Eastern Gate (Figure 2). Our excavations revealed a ditch running east-west 50 cm below the current ground level. The ditch was about 2 meters wide and filled with amounts of fine chips of laterite (1cm-0.5cm in diameter), suggesting the possibility of an approach. In addition, both sides of the ditch were covered with fist-sized sandstone cobbles.
For the purpose of finding the rest of this ditch as well as to verify the initial ground level, we opened a trench measuring 2 meters east-west and 2.5 meters north-south along the Eastern Gate and dug down. This trench revealed a sandstone cobbles covered surface that spread out over the entire surface 50 cm under the current ground level, and we were unable to detect any remains of the ditch.
We are planning another excavation in November to determine further details of the Eastern Approach and to identify the entirety of the newly discovered terrace-like remains.
One of the major charms of Ta Nei Temple is its ancient ruin-like setting, relatively untouched by human hand compared to other Angkor ruins. On the other hand, there is a need to prevent further collapse, in part to ensure the safety of visitors. Therefore, it is urgent for support structures to be installed and updated in a planned, organized manner on the basis of structural risk assessment of the overall temple complex. We decided to create elevation maps using SfM and conduct a risk assessment starting from the major buildings along the central axis. We started with two buildings with which we worked to establish the procedures for such operations. This work is currently being continued by APSARA staff.
To preserve the buildings and surroundings in good condition, as well as to help visitors to the area better understand the significance and value of the site, we wish to intensify our cooperation toward academic elucidation and achievement of effective conservation.
One of the lectures of the seminar
The seminar “Ancient Wooden Architecture In Mainland Southeast Asia: Reading The Features Of Lost Buildings From Archaeological Evidence” was held on 13 February 2017. In this seminar, experts from
Myanmar, Thailand, Cambodia, Vietnam and Japan made presentations on the developments on this field in each country, shared information and exchanged opinions.
In their presentations, the lecturers explained the different efforts being carried out in each country in order to determine the features of already lost wooden buildings from the remaining archaeological evidence. In Myanmar, large postholes shaped as wells and surrounded by bricks have been unearthed at the Bagan Royal Palace site. In Thailand, foundation stones, unearthed roof tiles, and traces of wooden members remaining in masonry walls and pillars have been used as hints to deduce the features of the wooden posts, walls and roof structures that existed in the sites of Sukhothai and the Phitsanulok Royal Palace. In central Vietnam, foundation stones, ornamental eave-end tiles and burned wooden members have been excavated from several Lin Yi sites, and reconstruction proposals of wooden structures have been developed on the basis of postholes found at the Champa site of My Son. Regarding northern Vietnam, the features of the foundation works and unearthed roof tiles at the Thang Long Imperial Citadel site were introduced, and a comparative analysis between earthenware architectural models and existing ancient buildings was made.
A question and answers session was held after each presentation, and at the end of the seminar a panel discussion with the participation of all the presenters was held, including the Japanese approach among the discussion topics.
The results of the fruitful exchange of information carried out during this seminar will serve as a basis for future cooperative research efforts, directed at furthering the understanding of the wooden built heritage of Southeast Asia.
On August 24th, 2016, a magnitude 6.8 earthquake with its epicenter in the central part of Myanmar struck; as a consequence, the ruins of Bagan, one of the representative cultural assets of the nation, suffered serious damage. The group of ruins in the region includes more than 3,000 brick Buddhist stupas and small temples built mainly in the 11th to 13th centuries. According to the Department of Archaeology, National Museum and Library, Myanmar Ministry of Religious Affairs and Culture, 389 of these sites were discovered to have been damaged (as of the end of October 2016).
Following the dispatch of an advance inspection team in September,2016, the Tokyo National Research Institute for Cultural Properties (TNRICP) was commissioned by the Agency for Cultural Affairs to oversee a project to provide emergency aid and sent a party of eight specialists (on conserving cultural assets, repairing buildings, structure of buildings, and surveying) to the sites with the aim of identifying the actual state of quake damage to valuable cultural properties, from October 26th through November 10th, 2016. They conducted surveys from four standpoints, namely, the situation of damaged historical buildings, the structural analysis of damaged buildings, the situation of emergency protective measures, and the analysis of records of damage.
The ruins of Bagan sustained quake damage in 1975 as well, and a large number of structures had been restored or rebuilt thereafter. As a result of the current inspections, however, it was discovered that much of the damage from this earthquake was concentrated on the newly reconstructed parts or the boundaries between the newly repaired parts and old parts, such as a tower of the upper part of a building. Moreover, deformation or cracks existing in vaults, walls or podiums owing to age are believed to have been aggravated by the earthquake. Meanwhile, thanks in part to prompt actions by local residents and volunteers under the leadership of local authorities, emergency protective measures appear to have been taken in an expeditious manner.
With an eye toward subsequent restoration, we must identify the cause and mechanisms of damage by not only conducting further inspection but also discussing the technical and philosophical issues that are common to the conservation of brick architectural heritages in earthquake-prone regions, such as how to reinforce a structure, melding of traditional techniques and modern counterparts, and the validity of reconstructing damaged parts.
