Zhao Donghui, Wang Xuetao/Xinhua Daily Telegraph
Looking from the outside, Yingxian Wooden Tower the west eaves of the second floor have sunk significantly and the pillars are tilted inward. Photographed by our reporter Xu Wei
Xinhua Daily Telegraph reported on October 19, "This tower is really a unique and great work. Without seeing this tower, I don't know the extent of the possibilities of wooden structure." The architectural master Liang Sicheng was amazed The national treasure is the Yingxian Wooden Pagoda located in Shuozhou City, Shanxi Province.
It stands majestically on the vast land of northern Shanxi. It is more than 20 stories high, octagonal in plan, with nine floors in total, five floors and four dark floors. The exterior has five floors and six eaves, and the bottom floor has double eaves with far-reaching overhangs. The whole pagoda is decorated with more than 50 kinds of brackets , just like a blooming lotus, and a Buddha statue is enshrined in the center of each bright floor. Climb the tower and take a look. The mulberry trunks are like a belt and the Hengyue is like a screen.
In the past thousand years, after experiencing wind and rain, earthquakes, wars, and improper maintenance, the world's tallest existing wooden pavilion-style pagoda has become distorted and deformed. In the early 1990s, the wooden pagoda renovation project was officially launched, but the renovation plan was "difficult" for nearly 30 years.
Industry experts believe that a scientific and prudent attitude must be adopted when repairing wooden pagodas, and they cannot be left to fend for themselves. Relevant departments should have the courage to take on the responsibility and form a powerful joint force to focus on solving the problem.
The world's tallest wooden pagoda is "very sick" Very serious
"Exquisite and majestic, leaning against the sky, the first construction of the floating map in the sea" "Like a peak rising from the ground, towering into the sky, thousands of trees subduing the Vatican Palace"... These praises Yingxian County The poem of wooden pagoda eulogizes the great creations of ancient Chinese craftsmen.
The Yingxian Wooden Pagoda, also known as the Sakyamuni Pagoda of Fogong Temple, was built in 1056. The tower is 67.31 meters high and is listed as the first batch of national key cultural relics protection units. It is known as the "Three Wonderful Towers in the World" together with the Eiffel Tower in France and the Leaning Tower of Pisa in Italy.
Chuta Ito, the founder of modern Japanese architecture, once compared Yingxian wooden pagodas with wooden pagodas in Japan in his book "History of Chinese Architecture": The many changes in the bracket system are due to the richness of the craftsmanship, which is different from that in Japan. Compared with the cookie-cutter method of using the same brackets on every floor, it is not clear which one is better and which one is worse.
The wooden pagoda also has many ancillary cultural relics such as Buddha statues, mural paintings, plaques and couplets, and inscriptions. In the second half of the 20th century, many precious cultural relics of the Liao Dynasty, such as Buddhist scriptures and "Medicine Collection Pictures", were also discovered in the pagoda.
However, this thousand-year-old pagoda built in the Liao Dynasty is "sick".
After being eroded by wind and rain, damaged by earthquakes, and destroyed by war, the wooden pagoda has been distorted and deformed. Especially in the 1930s, the mud-clad walls on the second to fifth floors of the wooden tower were artificially demolished, which had a serious impact on the structure of the wooden tower.
The reporter saw in "The Complete Works of Liang Sicheng" that in 1933, when Liang Sicheng, Mo Zongjiang and others from the China Construction Society first investigated and mapped the wooden pagoda in Yingxian County, they believed that "the current condition of the pagoda is not bad. Although there are some cracks." At that time, relevant people in Ying County wanted to build a pagoda, and Liang Sicheng was eager to join.
However, the wooden pagoda was quickly "renovated" without the participation of Liang Sicheng and others.
Originally, the upper four exposed floors of the tower were mud walls with diagonal braces inside, except for one of the four positive directions with a lattice door. After this repair, all the mud walls were demolished and replaced with lattice doors.
It turns out that local people who advocate building pagodas believe that the exquisite pagoda is not exquisite and destroys Feng Shui. Therefore, the mud wall was changed into a lightweight and ventilated lattice door.
Liang Sicheng deplored it repeatedly, calling it "the greatest misfortune of the wooden pagoda in more than 800 years." He believes that "this kind of plaster wall can protect against wind and rain, and the sloping beams can especially enhance the strength of the structure. Recently, the gentry in Yingxian County demolished the walls and replaced them with lattice doors. This not only destroyed the valuable ancient murals, but also changed the ancient architecture. The original shape will have a great impact on the maintenance of the tower. It must be restored to its original shape in the near future, otherwise it will only shorten the life of the tower."
More than ten years later, the "morbidity" displayed by Muta confirmed Liang Sicheng's worries. In 1950, when Mo Zongjiang, then an associate professor of the Department of Construction of Tsinghua University, joined the Yanbei Cultural Relics Survey Team to visit the wooden pagoda again, he found that it had been twisted and tilted, and some components were detached and split.
The reporter checked the "Report of the Yanbei Cultural Relics Exploration Team" written by Mo Zongjiang. He lamented in the book: "It has only been 14 or 15 years since the mud wall was demolished and replaced with a lattice door. The tower body can already be seen." The columns in the second floor are tilted most toward the northeast. The center of gravity of the upper part has moved away from the center, and most of the mortises on the column heads have become loose or damaged. Split due to tilt and torsion. If this situation is allowed to continue to worsen, it will be more difficult to repair and may even collapse suddenly. "After removing the mud wall, the lateral movement stiffness and torsional stiffness of the wooden tower will become smaller. Therefore, under the effects of wind load and vibration load, the deformation is greater than before," said Li Tieying, a professor at the School of Civil Engineering at Taiyuan University of Technology.
In 2004, the Shanxi Provincial Cultural Relics Bureau mentioned the "condition" of the wooden pagoda in its "Report on the Repair and Protection Project of the Wooden pagoda in Ying County": the pagoda body had been twisted and deformed, the load was unbalanced, and there was severe tilt and compression. Northeast tilt 65 centimeters, the tower body has been compressed by 88 centimeters in total, the north corner column on the west side of the outer trough on the second floor has sunk 20 centimeters, the south flat column on the southwest side tilts 50 centimeters to the northeast, etc. There are many component splits in the load-bearing parts of the lower part of the tower body. Dangerous situations include cracks, broken beams, and structural misalignment.
From June 1999 to May 2000, entrusted by the Yuanying County Wooden Tower Repair and Protection Project Management Committee, the original Shanxi Provincial Ancient Building Conservation Research Institute conducted a special survey on the damage condition of the wooden tower. The surveying and mapping alone lasted for 6 months moon. A cultural relics worker who did not want to be named told reporters that they worked hard at that time to survey and map the damaged components in dangerous and hidden places, and found more than 300 damage points such as splits, breaks, and defects.
"The wooden pagoda is indeed 'sick', and it is very sick." The cultural relics worker said.
Local reinforcement and protection work should be done sooner rather than later
In 2007, the China Cultural Heritage Research Institute became the technical lead unit for the wooden tower protection project. After more than ten years of monitoring, the institute found that in recent years, the tilt of the second-layer open layer has continued to increase steadily from southwest to northeast, but there has been no sudden change in the tilt deformation process.
At the Yingxian Wooden Pagoda Conservation Research Institute, Yong Xinqun, a research librarian at the China Cultural Heritage Research Institute, gave a detailed explanation of the monitoring results to reporters. He said that the deformation of the wooden tower continues to develop steadily. The largest deformation is currently on the southwest side of the second floor. Among them, the current tilt of column No. 23 is the largest. The tilt of the column measured in 2015 (the center of the column head relative to the center of the column foot ) exceeds 56 cm. In the past five years, its tilt and horizontal offset have also developed the largest, averaging more than 2 millimeters per year.
Yong Xinqun introduced that the tilt deformation of other columns generally decreases from southwest to northeast. There are individual columns on the north and northeast sides that tilt outward, so the deformation of the entire second-floor octagonal outer groove is pushed from southwest to northeast. state, the octagonal inner groove also has such a deformation trend. The tilt deformation of the second floor is reflected in the changes in the height of the column heads. Some column heads have settled due to inclination, while others have tilted upward due to outward inclination. This has also resulted in corresponding changes in the elevations of the columns on the upper floors.
"The tilt continues to increase, indicating that the wooden tower is not in a stable state. If targeted reinforcement and protective measures are not taken for severely tilted columns, they may become partially unstable, or even suffer partial or complete collapse in geological disasters." Yong Xinqun said.
The reporter stood due west and looked at the wooden tower. He found that the eaves on the second floor had sunk significantly and the columns tilted inward. Some columns were tilted severely, and many wooden components were cracked, split, detonated, and crushed. Because tourists were prohibited from climbing it for many years, the wooden tower has become a home for pigeons.
Yongxinqun believes that through monitoring in the past few years, the deformation shape, deformation characteristics and speed of the wooden tower have been basically understood. In this case, targeted local reinforcement and protection work with less intervention can be implemented sooner rather than later.
"On the one hand, it can play a role in disaster prevention, and on the other hand, it can buy time for in-depth research and preparation of a comprehensive and adequate repair plan." Yong Xinqun said.
No "prescription" can be given
The wooden tower has been "distorted" for at least 70 years.The reporter found out that in the 1970s and 1980s, the State Administration of Cultural Heritage organized experts to carry out rescue and reinforcement operations, but they failed to prevent the wooden tower from continuing to deform.
This renovation project includes reinforcing the base of the wooden tower, replacing the damaged floor slabs, reinforcing the main beams with holes, strengthening the split columns, repairing the brackets, remaking the flat base railings, and repairing the doors, windows, and fences of the wooden tower. Comprehensively repaired the tile roof, etc., and also renovated other buildings in the Buddha Palace Temple.
"When I was a child, the wooden pagoda was still in tatters. Someone fell from the upper floor to the next. After that repair, the railings, floor slabs, stairs, etc. have become stronger." Yuan Ying County Director of the Fogong Temple Cultural Relics Custody Office Dufour said.
However, there were mistakes in this repair. The reporter learned from the "Historical Experience in Repairing and Reinforcing Wooden Towers in Yingxian County" written by Meng Fanxing and Zhang Changgeng that the two triangular supports of the "temporary roof" were in the wrong position, which was counterproductive and caused more harm than good.
On the evening of October 9, the reporter met Zhang Changgeng, an 85-year-old cultural relics worker in Datong City, Shanxi Province. He was familiar with the rescue and reinforcement project of the wooden tower. The old man said frankly: "There were indeed mistakes during the maintenance, and many remedial measures were taken later."
In the early 1990s, the repair and protection work of the wooden tower was once again put on the agenda. But because of the controversy, it never came to fruition.
The reporter consulted the archives of Ying County Culture and Tourism Bureau and learned that the research and protection of wooden pagodas has gone through two stages in the past 30 years. The first stage started in 1991 when the wooden pagoda maintenance project in Yingxian County was officially established, and in 2006 the "upgrading and repair" plan was suspended. The second stage begins in 2007 when the China Cultural Heritage Research Institute became the technical lead unit for the wooden pagoda protection project.
Whether it was the overall repair plan in the first phase or the partial reinforcement plan in the second phase, they were not implemented due to controversy.
From the establishment of the Ying County Wooden Pagoda Repair and Protection Project Management Committee in 1999 to 2004, the relevant cultural relics departments have invited more than 50 experts to inspect the wooden tower on site, and commissioned 23 universities, scientific research departments, and survey and design units to complete 40 A number of preliminary survey projects were carried out, and on this basis, they came up with plans such as "falling frame overhaul", "current situation reinforcement", "lifting repair", and "steel bracket support". Experts debate the pros and cons of different options.
Deputy director and chief engineer of the Yingying County Wooden Pagoda Repair and Protection Project Management Committee Chai Zejun once analyzed these four repair methods for reporters during his lifetime: "Falling overhaul" is relatively mature in implementation technology and can be thoroughly implemented. The damaged components are reinforced at the bottom to correct distortion and deformation, but the component replacement rate is large, and the storage and fire-fighting tasks of dismantled components are also huge;
"current situation reinforcement" saves a lot of historical information, but cannot fundamentally solve the damage and deformation of the wooden tower. disease, poor reinforcement may cause greater trouble;
"lift repair" is to lift the upper part of the wooden tower that is less dangerous, and use traditional repair methods to dismantle and repair the lower part of the tower, which can fundamentally repair the lower part of the wooden tower. symptoms, More historical information is retained, but the lifting device has high technological content, is complex, difficult, risky, and requires a large investment;
"support repair" uses steel frames between the inner and outer groove columns of the wooden tower to support the wooden tower. , loaded by the steel frame. The tower body, platform foundation and the weight of the steel frame installed in the tower will cause greater harm to the foundation of the wooden tower. The use of steel frames to support the tower will cause more damage to the main load-bearing components of the wooden tower, causing changes in the internal load-bearing system of the wooden tower and changing the original appearance of the wooden tower.
In order to carefully select the restoration plan, in 2002, with the approval of the State Administration of Cultural Heritage and the Shanxi Provincial Government, the Ying County Wooden Pagoda Repair and Protection Project Management Committee held a plan review and demonstration meeting in Taiyuan, with 7 academicians and 34 experts participating. The meeting adopted a registered vote and determined that the overall idea of the wooden tower repair plan is "upgrading and repair." In 2003, the State Administration of Cultural Heritage approved this idea and related projects.
However, in 2006, the State Administration of Cultural Heritage held an "Expert Review Meeting on the Yingxian Wooden Pagoda Uplift and Repair Plan" in Shuozhou City, Shanxi Province, and considered that the "Yingxian Wooden Tower Earthquake Reinforcement Plan" and the "Yingxian Wooden Tower Protection Project Uplift and Repair Plan" is not mature enough as a project implementation plan and does not meet the conditions for implementation.In addition, the existing work results have not yet fully analyzed and researched the current situation of the wooden tower, especially the safety situation. There is a lack of particularly convincing scientific judgments, and the method of repair needs to be further studied. Therefore, both plans are on hold.
In 2007, the China Cultural Heritage Research Institute took over the early results and became the technical lead unit for the wooden pagoda protection project. In response to the continuing development of the wooden pagoda, at the end of 2014, the reinforcement project of the severely tilted parts and severely damaged components of the wooden pagoda in Yingxian County was launched, but was later stopped by the State Administration of Cultural Heritage due to unclear results.
From 1992 to 2001, Du Fu, then director of the Fogong Temple Cultural Relics Custody Office in Yingxian County, went to the Daxinganling Mountains to purchase wood for the overhaul of the wooden pagoda. Because the other party required remittance first before shipping, the superiors were afraid that it would not be safe and did not make the purchase. The wood purchased later was stored in the Buddhist temple.
In order to ensure the fire safety of the wooden tower, as the repair of the wooden tower was delayed, the wood was moved to the local lumber factory by his successor Qin Liangtai. During his seven years as director, Qin Liangtai happened to catch up with the time when the maintenance and protection of wooden towers received the most attention.
"I think the main reason is that there is no unified opinion. There is no absolute authority or expert who has said that we will repair it according to this plan." Qin Liangtai said that it is time to take action. The distortion and deformation of the wooden tower can be corrected at best, and at least if it cannot be corrected, It should be protected and not allowed to twist anymore.
"If it continues without construction, will it become more deformed? What will be the consequences?" Qin Liangtai was worried.
"Unbearable Heavy" Repair System
This high-rise wooden tower that has withstood thousands of years of wind and rain is a rare treasure and the only example in the country. However, its current conservation research strength is relatively weak.
According to the relevant provisions of the Cultural Relics Protection Law, local people's governments at all levels are responsible for the protection of cultural relics within their own administrative regions. However, Yingxian County, where the wooden pagoda is located, is an agricultural county. In 2019, the general public budget revenue was less than 180 million yuan. It is under great pressure to improve the environment around the wooden pagoda and demolish illegal buildings.
Local financial resources also restrict the development of the "second battlefield" for wooden tower research and the protection of its associated cultural relics. According to a person in charge of Ying County, on the one hand, because the plan to repair the wooden pagoda has not been approved, some experts proposed to open a "second battlefield" in Longshou Mountain, 8 kilometers away from the wooden pagoda. Center, build an experimental wooden tower with a 1:1 ratio as a to accumulate experience and cultivate talents for the maintenance of wooden towers; on the other hand, Yingxian County also plans to build a museum of ancient Chinese wooden structures in Longshou Mountain. The remaining precious cultural relics of the Liao Dynasty provide a safe collection environment. But both ideas are subject to financial constraints.
The Yingxian Wooden Pagoda Conservation Research Institute, a specialized protection and management institution for wooden pagodas, is a stock-level institution under the Yingxian County Culture and Tourism Bureau, with 28 formal staff. The original main responsibility of this organization was "fire prevention, theft prevention, and vandalism prevention." Now it wants to capture research and cultivate a team of talents that cannot be taken away.
"The research has just started. It is difficult to recruit talents due to the influence of region, establishment, level, etc." said a person familiar with the matter. Since
became the technical lead unit of the wooden pagoda protection project, the China Cultural Heritage Research Institute has undertaken most of the work of protecting and repairing the wooden pagoda. However, due to constraints of manpower, conditions, capabilities and other factors, it is difficult for individual soldiers to form a joint force.
In the past ten years, they have mainly carried out structural deformation monitoring, roof hook maintenance, wooden tower protection planning and other work, but it is difficult to fundamentally alleviate the wooden tower's condition. In the near future, they will also implement 9 projects including detailed surveying and information retention of wooden towers, deformation monitoring, protection of wooden tower plaques and couplets, research on the history of wooden tower construction, and adjustment and optimization of wooden tower reinforcement plans.
At present, the institute's power to invest in wooden tower protection research is also weak. Dean Chai Xiaoming said that in order to "treat" wooden towers, experiments need to be done first. However, the hospital's cultural relics science and technology equipment is currently backward, and there is a great need to strengthen the construction of large-scale experimental equipment and equipment.
"There are only two or three people in the hospital who are responsible for the wooden pagoda full-time, and there is no clear designated general person in charge. It is sometimes difficult for ordinary scientific researchers to do coordination work." Yong Xinqun said.
Regarding the main contradiction of the "distortion and deformation" of the wooden pagoda, some experts said that the "discussion but no decision" is ultimately due to insufficient basic research on the wooden pagoda and unclear understanding of the wooden pagoda.
Some experts pointed out that the digitization of cultural relics is an important means of cultural heritage protection and an important way to achieve permanent protection of cultural relics information. However, at present, the digitization work of wooden pagodas has not been fully carried out; under the huge pressure, the traditional method of repairing the old as before, The repair method of seams and patches is difficult to work. The three-story beams and bucket-type wooden components under the wooden tower need to be replaced. This will inevitably be opposed by many people. It also requires convincing investigation materials for each wooden component. .
Li Tieying said that there is currently no quantitative basis for judging how much the wooden tower will tilt before it collapses. Answering this question requires experimentation, which people are generally unwilling to do because it costs too much.
In addition, "people's understanding of the structural performance of ancient wooden buildings is relatively weak, and errors are prone to occur during the repair process." Li Tieying said, for example, if the old pillars have been pressed for nearly a thousand years, will the new pillars be able to match the old ones after being subjected to heavy pressure? Are the pillars generally high? The combined use of new and old components also requires in-depth testing.
Looking forward to leaving no regrets
Many interviewees said that the Yingxian wooden pagoda is an unparalleled treasure of ancient architectural art. We should seize the time now and summon the best "doctors" to study the "illness" to prevent the "illness" of the wooden tower from being delayed in the "cutting" protection work of individual soldiers fighting.
Some experts said that protection and research should be further strengthened. Relevant departments should systematically sort out the existing research results of wooden pagodas, formulate several major issues that need to be overcome in the repair and protection of wooden pagodas, and list them as key issues for the State Administration of Cultural Heritage and Shanxi Province. work, convene the country's top professional forces with an open attitude, advocate cross-field and multi-disciplinary cooperation, form synergy, and focus on solving problems.
Li Tieying believes that the preliminary basic investigation work for repairs is very important. From the top to the bottom of the tower, each wooden component needs to be "diagnosed" before repair to determine whether it should be retained, repaired or replaced. Based on the judgment of various types and layers of wooden components, an evaluation of the overall structure of the wooden tower is finally formed, and a repair method is provided.
"The investigation cannot be done by novices. It must be done by people who have experience in the structural performance of ancient wooden buildings and are familiar with the repair methods of ancient buildings, so that scientific and reasonable judgments can be made." Li Tieying said.
In terms of specific implementation, Li Tieying suggested that the State Administration of Cultural Heritage adopt a project delegation system to specify the projects useful for the renovation of wooden pagodas and assign them to dedicated personnel. For example, there are experts who are responsible for conducting model tests to determine how much the Yingxian wooden tower will collapse if it deforms further; there are experts who are responsible for investigating all the wooden components of the wooden tower; there are still people who are responsible for organizing reviews and reviews, and strive to make the work effective and reasonable. "The experts we find are very important. We must objectively evaluate who can do the job well, and the funds must be arranged in a reasonable way so that the people who are actually doing the work cannot suffer losses," he said.
Chai Xiaoming suggested opening up a "second battlefield" for wooden tower research, taking the opportunity of building an "experimental tower" to gather the best teams in relevant majors across the country to collectively tackle key problems. On the basis of research, scientific repair work should be carried out as soon as possible to prevent the wooden tower from continuing to tilt.
Many interviewed experts held similar thoughts. Li Tieying said: "This job is very useful. Many things will be understood during the construction process. Some people are still afraid of taking risks when building wooden towers directly. Once they have experience, they can build wooden towers in reverse."
, a long-term construction worker Shanxi makes cultural relic rescue records, Scholars who investigated emphasized that every renovation interferes with the historical information of the wooden pagoda. It is recommended that before the renovation is carried out, the digital protection work of the wooden pagoda should be carried out as soon as possible, and digital archives should be retained for the wooden pagoda. Detailed archaeological surveys have been carried out on the numerous Buddhist relics in the pagoda.
Regarding the water supply and drainage around the wooden tower, the demolition of illegal buildings, and the construction of the wooden tower museum, Yingxian County hopes to receive more financial support from higher-level governments to eliminate safety hazards caused by the surrounding environment. The local area also hopes that the country, provinces and cities will provide support in earthquake monitoring and early warning, disaster prevention guidance and other aspects.
"Only when the top scholars and engineers in the relevant fields conduct long-term research on the wooden pagoda and clarify the key issues will a repair plan come out." This is the expectation of a scholar in the field of cultural relics protection.
The editor of this issue Zhou Yuhua
