The results and outcome from the experience of the 3 restoration sites of JSA has lead to the fundamental idea of the technical restoration method for Bayon.

Conservation and Restoration works are largely affected among the types of building, the structural method of the past, and how far the building is damaged. Through out the restoration works at the three sites of JSA, we have cultivated different techniques for each. Cutting through the stereotype restoration, our policy is to devote ourselves to the research of the techniques, and this is succeeded to the restoration of the entire Bayon complex.
Partial Dismantling and Reassembling of the Northern Library of Bayon
  • Partial Dismantling and Reassembling, especially developing the new construction method of the foundation
The roof and walls had been deformed considerably due to uneven settlements it was obvious that dismantling and reconstruction was required. Disintegration of the east and west corners were beyond repair, however, as the central part of the foundation mass sank comparatively evenly over a wide range, we adopted the method which is to leave the central part of the foundation as it is and dismantle only the corner edges of the building.
Also we reassembled the compound soil layer by applying the method of "TATAKI"(traditional Japanese method for making a Compacted Sand Layer). With this method, sandstone and laterite blocks fulfill both ornamental and structural functions of the construction material used in the past. It was JSAs proposition, preserving not only the appearance but also respecting the original construction and structural method, while on the other hand adopting a method that will overcome the weak point of the original structural system.
(left) Strength and endurance test of many kinds of soil samples, made of various mixture proportion with sand, soil, slacked lime and water

( center) Dismantling the foundation mass partially and reassembling (repair and reconstruct the sandstone of the foundation mass, replace the damaged laterite blocks and repair the sand layer inside the foundation mass)

Restoration of Prasat Suor Prat and terraces at the Royal Plaza of Angkor Thom
@@(continued since May 2001)
  • Dismantling the whole structure including its platform and foundation
  • Restoration and reassembling of damaged laterite blocks
The restoration of N1 Tower, which had been deformed considerably, started from research and analysis of the situation of deterioration and collapse. After the investigation, and also because the collapse of many Angkor monuments is presumably caused by the structure of the platform and foundation, we have decided to dismantle the whole structure of the building including its platform and foundation for the first time in Angkor. We can grasped precious data for research works for the future conservation and restoration. The results of research will be reflected to the actual restoration works.For the damaged laterite blocks, we have established a suitable manual through out destruction and mortar tests in order to give sufficient strongness and endurance when reassembling.
Restoration of Northern Library inside the Outermost Enclosure of Angkor Wat
@@(continued since Oct.1999)
  • Re-restoration of the former restoration
  • Returning back of the repaired original materials
Today we see mortar and concrete already been used to repair the entire Angkor Wat complex. But JSA has an basic policy of employing traditional methods of construction and also conserve by repairing original materials as much as possible and returning them back to the original position. We use sandstone, whose procurement has newly become possible, and are undertaking the conservation and restoration of the Northern Library by always considering the harmonization of the former restoration.