Influence of microclimate on the directional dependence of sandstone pillar weathering in Angkor Wat temple, Cambodia

Abstract

Angkor Wat temple, mainly composed of sandstone blocks, displays a type of religious architecture that signifies the worldviews of the Khmer and Hindu religions. The temple is a part of a UNESCO World Heritage site. However, there are numerous occurrences of hollows, i.e., depression-like notches, that have developed at the base of its sandstone pillars due to wet–dry and salt weathering. These pillars are variably weathered due to differences in the directions of the pillar surfaces and galleries in the temple. In this study, we analyze the differences in the hollow depths based on the sandstone hardness and water content, as well as a 5-year record of the temperature and humidity in the galleries. The results show that the hollow depths are profound in the outsides of the inner pillars and shallow on the northern side of the first gallery. The hollow depth increases with increasing values obtained by multiplying water content and moisture fluctuations, resulting from direct insolation together with rainfall.