The investigation conclusions of major bridge accidents in recent years have not identified a quality reason

The breaking accident of Harbin Yangmingtan Bridge hurt the public's nerves again. The bridge has been in use for less than 1 year since it was built and opened to traffic.

According to statistics compiled by this newspaper, there have been 15 publicly available bridge collapse accidents nationwide in the five years since 2007. A total of 141 people were killed, 111 injured and 18 missing. Of the 15 bridges where the accident occurred, only 3 had been in use for more than 15 years at the time of the accident.

Despite the public's many doubts, in the above-mentioned official investigation conclusions, there is no clear incident that is related to the quality of the bridge itself. Many industry experts, including Chen Zhaoyuan, an academician of the Chinese Academy of Engineering, publicly stated that the frequent occurrence of bridge accidents is "congenitally deficient and destined".

Only 15 of the 15 collapsed bridges have been built over 15 years

The casualties caused by the collapse of the bridge in recent years have been shocking. According to the statistical analysis of the public information in this newspaper, it was found that 15 bridge collapse accidents in the past 5 years have caused 141 deaths, 111 injuries and 18 missing.

Among them, the most serious was the collapse of the Tuojiang River Bridge in Hunan.

At about 17:00 on August 13, 2007, the Tuojiang Bridge under construction suddenly collapsed, causing a total of 64 deaths and 22 injuries. The State Administration of Work Safety determined afterwards that the accident was due to the violation of relevant regulations by the Hunan Xiangxi Autonomous Prefecture Government during the approval process of the Tuojiang Bridge construction project, and required the State Planning Commission and the State Transportation Bureau to rework and reverse the relevant documents; The "Zhouqing" gift was a major liability accident.

At 17:20 on July 24, 2010, the casualties caused by the collapse of the Yihe Bridge in Luanchuan, Henan, were also shocking. As of August 6, that year, the official confirmed that 53 people were killed and 13 were missing.

According to the above statistical calculations, an average of 15 bridge collapse accidents in the past five years will cause 18 casualties or disappearances.

Of the 15 accidental bridges, only three had been in use for more than 15 years.

Three bridges under construction collapsed. In addition to the above-mentioned Hunan Fengtuo Tuojiang Bridge, which caused heavy casualties, the Liaoning Fushun Crescent Island West Cross River Bridge collapsed at 17:21 on June 18, 2012. When it collapsed, the bridge was about to be completed. The collapse of the bridge under construction at Kunming New Airport occurred on January 3, 2010.

Except for the above six bridges, and the Harbin Yangmingtan Bridge that has been completed and opened to traffic less than one year and has had an accident recently, the remaining eight bridges have been in use for 12 to 14 years. Statistics show that the bridges that have been in use for 12 to 14 years after completion are accident-prone bridges.

The official investigation conclusions did not clearly have quality reasons

In the above-mentioned collapse accidents with public investigation reports or conclusions, this newspaper did not find any investigation conclusions to clarify that the accident was caused by the quality of the bridge itself.

The accident of the Hunan Tuojiang River Bridge was identified as a major liability accident caused by the rush of construction and other reasons. The collapse of the Hongqi Road viaduct in Zhuzhou, Hunan Province. The Zhuzhou Municipal Government reported that there was a human factor, which was caused by the suspects winning the bidding by anchoring without the corresponding qualifications. The collapse of the West Cross River Bridge in Crescent Island, Fushun, Liaoning, which occurred in June this year, was eventually determined to be caused by illegal operations.

As of August 6, that year, the overall collapse of the Luanchuan Yihe Bridge in Henan confirmed that 53 people were killed and 13 were missing. According to media reports at the time, local officials claimed that the accident was caused by a heavy rainstorm that caused the overall collapse. Some media reported that no steel bars were seen on the collapsed bridge decks and exposed bridge piers at the scene, and the only two steel bars that were seen were nobody's fingers thick. However, the newspaper did not have access to the investigation report of the accident.

As with the overall collapse accident of the Luanchuan Yihe Bridge in Henan, there were two other local authorities who determined that the weather was the main cause of the accident.

At around 7:10 pm on May 8, 2010, part of the deck of the Hongni Bridge in Fuling, Chongqing collapsed, causing one person to be seriously injured. The official investigation stated that the accident was mainly caused by continuous rainfall. In addition, the bridge's long-term overload operation caused the junction pier to cause tilt displacement due to the slip of the red clay interlayer, which is also an important reason for the collapse of the bridge. The collapse of Fangu Bridge in Pingjiang, Hunan, where two people were killed and four people whose whereabouts are unknown. The official reason for the accident was the local sudden flood, and the upstream sand boat was washed down by the flood and hit the bridge pier. Because no reinforcement was found in the bridge fragments, some villagers questioned whether the bridge had quality problems. In response, Mao Shuainan, director of the local transportation bureau, said that the bridge is a three-hole open-web stone arch bridge, which supports the bridge body through a geometric mechanical structure, does not require reinforcing steel, and there is no quality problem for the collapsed bridge.

There were 4 accidents that were clearly identified or mentioned that the vehicle was overloaded and overrun as the cause of the accident. The four accidents are: Chongqing Fuling Hongni Bridge Collapse Accident, Jilin Jinjiang Bridge Collapse Accident, Fujian Wuyishan Mansion Bridge Collapse Accident and Hangzhou Qianjiang Third Bridge Partial Deck Accident.

It should be noted that the investigation report on the collapse of some bridge decks of the third Qianjiang Bridge in Hangzhou stated that there was a hidden danger of “stressing of hollow slab beams and single slabs” before the accident occurred. The failure of relevant units to repair it in time was also one of the reasons for the accident.

However, the local Hangzhou report did not specify whether the Qianjiang Third Bridge itself had quality problems. According to the China News Network report, on September 13, 2006, Zhu Yulong, chief engineer of the Hangzhou Municipal Transportation Bureau, as the team leader of the Hangzhou Qianjiang Third Bridge Overhaul Engineering Specialized Chair, held an expert meeting on Hangzhou Qianjiang Third Bridge Overhaul Engineering Technical Issues. The minutes of the meeting showed that the Qianjiang Third Bridge had serious engineering quality problems.

Two collapse accidents in Yunnan and Xinjiang are believed to be caused by the long-term disrepair of the bridge. In addition, there were two accidents in which the newspaper failed to consult relevant investigation conclusions.

After the accident of the Harbin Yangmingtan Bridge, despite many doubts from the outside world, the local government and relevant experts initially gave a conclusion that the accident was directly related to the vehicle overload, and did not mention the accident and the bridge There may be a correlation between the quality of itself.

Accidents are frequently "destined"?

Officials in many places refer to overload and overrun as the main cause of the accident. Industry experts admit that this is one of the direct causes of the accident, but the hidden quality of the bridge itself is the main cause of frequent accidents.

Li Fengqin, a representative of the National People's Congress and a senior engineer of the Bridge Division of the Third Railway Survey and Design Institute Group Co., Ltd., is the structural designer of many railway bridge projects such as the Lhasa River Bridge of the Qinghai-Tibet Railway.

In her view, if the vehicle is overloaded and the stress on the bridge exceeds the designed safety factor, the bridge may collapse immediately. "Even if the overloaded vehicle fails to crush the bridge, it may cause cracks on the deck, fatigue problems such as booms, anchor heads, etc." Li Fengqin said in an interview with the media that the overload of the vehicle is very harmful. "Bridge design life is generally In 100 years, if overloaded vehicles pass frequently, the bridge may reach its design life in less than 10 years. "

In an interview with the media, Shi Xuefei, director of the Bridge Construction and Information Technology Research Office of Tongji University and a director of the Bridge and Structural Engineering Society of the China Highway Society, also described the hazards of overloaded vehicles to the service life of bridges. He said that the actual load of the trucks currently used in China is significantly greater than the load weight specified in the code. "This is mainly caused by illegal modification. The car manufacturer will design the load capacity to be very large, but it is very low when it is reported to the management department for finalization. These are not known by the management department. The bridge can adapt to the legal car load, cannot Meet illegally increased loads. "

After the collapse of the Yangmingtan Bridge in Harbin, the Lugou Bridge, which has stood up to the ground after nearly a thousand years of wind and rain, reappeared in the eyes of the public: In January 1957, Beijing ’s cultural relics, transportation, municipal design, infrastructure and other departments Carrying capacity for scientific experiments. The results of the experiment showed that the oversize large-size flatbed truck weighing more than 400 tons passed the ancient stone bridge safely. The weight of the Lugou Bridge during the experiment was exactly the same as the total weight of the overloaded vehicles initially announced by the Harbin government.

Built over eight years, the Nanjing Yangtze River Bridge, which has been in service for 44 years, has been subjected to more severe tests. When the bridge built with the collective wisdom of national bridge experts was initially completed, Xu Shiyou, who was the commander of the Nanjing Military Region, had transferred nearly 100 tanks to drive across the deck at the same time to test the quality of the bridge.

The pier of Wuhan Yangtze River Bridge, built in 1957, was hit by a 10,000-ton oil tanker on June 6, 2011, but it was almost unscathed. The bridge has been hit by more than 70 times since it was opened to traffic, but it still guarantees the normal passage of trains and motor vehicles.

Chen Zhaoyuan, an academician of the Chinese Academy of Engineering and an expert in civil engineering structure and protection engineering, once pointed out in an open letter titled "Is the bridge collapse speed too fast?" The frequent occurrence of accidents and the short life of engineering facilities are "congenitally inadequate and destined" .

Academician Chen Zhaoyuan took the Qianjiang Bridge, which was built in the 1930s and designed according to international common standards and is still unharmed under the condition of overloaded services, as an example to point out that some engineering design, construction codes or standards in China are too low to bury the accident. "Taking the housing construction as an example, the load-carrying capacity of the floor load required by the design codes of our country is only about 50% -60% of the international general standard. The minimum thickness of the protective layer required for the corrosion of steel bars in the concrete structure is only the international general standard. Half. Therefore, the frequent occurrence of accidents and the short life of engineering facilities can only be congenitally insufficient, and it is destined to be doomed. "Chen Zhaoyuan said in an open letter.

In this open letter, Chen Zhaoyuan pointed out three deep-seated reasons behind the frequent collapse of bridges: First, whether our construction speed is too fast, many projects are objectively impossible to achieve elaborate design and careful construction, sometimes In addition, due to the need to complete the gift in advance, in addition to violation of market rules, some public construction costs are not in place. Secondly, the poor quality of the project is due to the low minimum requirements of China ’s engineering design and construction technical specifications or standards. After the completion of the project, it is inherently inadequate and cannot be put to death. Third, there is a lack of regular testing and maintenance during the long-term use of the project. Some accidents could have been avoided and could not be reinforced in time.

Shi Xuefei also pointed out that the over-practical bearing capacity in project construction, rush-duration, industry protection, corruption factors in project construction, and insufficient competition are also one of the important reasons for the frequent occurrence of new bridge accidents.

The construction period is always the main theme in the construction of Yangmingtan Bridge. It took only 18 months from the start of construction to the opening of the bridge. On the day the bridge was built, Heilongjiang News Network once said that the bridge construction task of the planned three-year period will be completed in 18 months, and the Yangmingtan Bridge "has become the fastest super-large cross-river bridge in China."

On the second day after the bridge was opened to traffic, an article in Harbin Daily wrote: Once, a famous bridge expert "advised" the Yangmingtan Bridge construction team: "You can't complete the construction schedule." Now, These "advisories" all become "floating clouds". In response to the fact that the bridges were used for 12-14 years when the accident occurred, Li Fengqin pointed out that most of the bridges that collapsed were not newly built, but were built in the late 1980s and early 1990s. "At that time, the construction market was chaotic. Some people took advantage of the loophole and cut corners during the construction process. The construction quality problems were exposed with the collapse." Li Fengqin said.

For this reason, the Global Times specially published an editorial saying: The collapse of all new bridges is without exception an accident of responsibility, and they all collapse in the management of the construction and use process. "People's Daily" official Weibo voiced on the evening of the 25th, suggesting that the local government "for the release of accident information, objective and timely disclosure, rather than giving people the suspicion of shifting responsibility and shifting the focus of public opinion. Persuasion is not difficult. Publishers must first think differently: as an ordinary person, you need to understand what you need to know, and then you have to say one thing and truly respect facts and common sense. "

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