Parts of 600-year-old structure could collapse in heavy rain: curator
A major restoration project to protect the walls of the Palace Museum in Beijing, also known as the Forbidden City, began Saturday, which aims to fix the diseases of "old age" that threaten the 600-year-old imperial structure.
Museum curator Shan Jixiang said the outer wall, which is 3,437.6 meters in length, has many "diseases," including decaying and crumbling bricks, cracks in the structure and subsidence that is undermining its foundations, The Beijing News reported.
It is the biggest restoration project at the museum since 1949. The first phase has already begun on a 233-meter section of the wall at the western end of the complex named Xihuamen, which is the part most affected.
The Xihuamen section has been repaired twice since the 1950s, Shan said, noting that despite the restoration, severe damage to the wall was still found in 2013, and the bricks were badly fractured in 2014.
Since the Forbidden City is well-preserved, these problems are mainly caused by natural factors, such as climate change and acid rain, Tian Lin, a professor of ancient architecture at the Beijing University of Civil Engineering and Architecture, told the Global Times.
Shan told The Beijing News that the renovations are urgent as the wall is in such a poor state, it could collapse in heavy rain.
Experts on the Forbidden City said that ground-penetrating radar will be used to guide the renovation work, assisted by other methods to detect what lies inside the wall. After the survey process, the wall will receive a new waterproof coat, damaged bricks will be replaced and the foundations will be reinforced.
Wang Guixiang, a professor of ancient architecture at Tsinghua University, stressed that "the renovation work should strictly follow the record."
Meanwhile, Tian noted that the repairs should stick to the "minimal intervention" principle, which requires "the original material, original technology and original way of building." However, Tian added that it is impossible to make the repairs consistent with the original style, as while they know what techniques were used, it is impossible to reproduce them accurately.
Shan said that currently, the Forbidden City is working on its plan to repair the whole wall and it will be open to the public gradually after the project is completed.
Apart from the wall, a project to improve the Forbidden City's infrastructure - including its plumbing, wiring and heating - will proceed at the same time. Currently, the infrastructure is outmoded and its supply capacity is insufficient, said the report.
The Forbidden City announced a visitor limit of 80,000 a day from June 13, 2015. The huge number of visitors makes conservation efforts difficult and the ancient architecture and relics suffer from such large crowds.