Proactive Conservation of Main Tower of Bayon, Angkor, Against Global Warming

This paper describes the special characteristics of the ancient temples in Angkor in terms of geotechnical points of view, which have never been mentioned in the past because simply the soils and foundations have never been studied. Japanese Government Team for Safeguarding Angkor (JSA) introduced the study of soil and foundation. The heritage structure of Bayon in Angkor stands upon shallow direct foundation. The high main tower stands upon manmade fill of 14 m in thickness without special supporting such elements as piles. The amazingly strong strength of the manmade fill that had made to support heavy stone structure is the one of the character-defining elements of the authenticity of the foundation of Bayon in Angkor Thom. If the sand fill shows the shear strength of the common sandy, the fill could not keep standing safely under the rainy season in the south Asian region of the squall with heavy rain for the last 700 years since thirteenth century. To preserve the main stone tower, the paper proposes a simple method to cover the surface of the fill of the mound with impermeable layer to prevent the failure of the sand filled mound from the anticipated long and heavy rain in the coming global warming.