The Apsara National Authority (ANA) said the second phase of restoration is underway at Prasat Tonle Sgnuot – the ancient hospital built during the reign of King Jayavarman VII in the late 12th century and early 13th century.
Located in Nokor Krau village, north of the Angkor Thom enclosure, the first phase of restoration was successfully completed in July last year.
In a Facebook post on Wednesday, the ANA said that in the first phase, experts conducted research, listed scattered stones, planned their assembly and removed loose stones from some parts of the temple’s roof and foundations.
The post said in the second phase this year, the working group will continue excavation and start repairing and reinforcing foundations.
It also aims to assemble the terrace stones in the temple body up to the 15th layer of the lintel, with the third and final phase of the project scheduled for next year.
“After [the ancient hospital] was studied and assessed architecturally, a working group decided that, given their findings and recommendations from Unesco experts, repairs needed to be prioritised immediately.
“The ANA senior leadership approved the move, and repairs to the roof and its foundations were carried out using a reconstruction technique called anastylosis.
Anastylosis is a process whereby a ruined building or monument is restored using the original architectural elements to the greatest degree possible.
Chea Sarith, the archaeologist at the Department of Conservation and Archaeological Preservation in Angkor Archaeological Park, who is also the project head for the Prasat Tonle Sgnuot restoration, said studies showed the ancient hospital faced collapse due to water impact, surrounding tree growth and ageing materials.
He said the building’s main body had weakened, causing it to tilt towards the western corner over 15 degrees, triggering varying structural damage.
“Holes can be found between 5cm and 45cm wide across the structure, while large parts of the stone walls and the roofs at the southeastern and north-western corners have eroded and fallen to the ground.
“To rebalance the structure, we had to reinforce the foundations, the terrace and the body of the building in compliance with technical standards and ancient materials,” he said.
Sarith added that based on the study, the working group had not removed all of the foundations completely, but just the necessary parts.
“The decaying stones were removed, and replaced with new good quality stones. We used wooden wedges to support and raise up old stones to ensure we fit new stones into the original patterns of the structure.
“The working group could not remove all the original stones completely to retain the level of the original height and the original locations of each stone.
“After preparing to assemble the stones from the first to the third layer and a series of layers to fit in the original patterns, the working group had to remove the stones up to the first layer and replace decayed sandstones with new stones according to the recommendations by Unesco experts,” he said.
Chea Socheat, another archaeologist at the Department of Conservation and Archaeological Preservation in Angkor Archaeological Park, said that the excavation of the ancient structure’s foundations was very useful in preparation for foundation repairs.
He said the study showed that Prasat Tonle Sgnuot was not built on natural land, but the original builders had fabricated the foundational land mass using a range of materials, some of which were biodegradable.
“The foundation pits were filled with layers of sand, clay, mountainous stones and tree roots. So, the main reason leading the building to sink was due to the decomposition of tree roots in the mixtures of dirt which made up the foundations,” he said.
The ANA said that after the first phase of excavation had been completed last year, the experts discovered the original foundations of the hospital.
Excavation showed that the hospital was around 31m long and more than 20m wide when originally built. However, large parts of the original walls had been lost over time.
He also said that during excavation they had spotted small broken porcelain pieces deep in the soil.