A piece of soil or a stone, moved from the field to the laboratory, is the same in the eyes of others, but in the eyes of Tan Qinwen, there is a world of difference.
Li Changdong is a professor at China University of Geosciences (Wuhan). He and Tan Qinwen are colleagues at China University of Geosciences. They are also members of the research team of Tang Huiming, chief professor of geological engineering at China University of Geosciences. The topic studied by Li Changdong and Tan Qinwen is called "Evolution Mechanism and Prevention of Geological Disasters." Simply put, they hope to predict landslide geological disasters like weather forecasting.
Drilling deep into the mountains to eat pickles, field monitoring for half a year
A few days ago, in a group of 908-meter-deep tunnels excavated manually in the heart of a large mountain in Badong County, Hubei Province, Tan Qinwen carefully cut out 0.5 meters of soil on the slope of a landslide fault. We installed various instruments on a 0.5 meter The situation must be observed in situ," Tan Qinwen said. In-situ observations measure objects in the most restorative way compared to laboratory observations.
For the in-situ rheology test of slippery soil, the machine had to be turned on 24 hours a day, and people were never left behind. Tan Qinwen and his companions monitored this 0.25 cubic meter soil block for 180 days. They went into the cave at 7 a.m. with breakfast and lunch of dry food and pickles, and left the cave at 7 p.m. for a hot dinner. Their life of "in situ observation" started over and over again.
Associate Researcher Tan Qinwen tells the story of the field test of the Huangtupo landslide tunnel group in Badong. Photographed by Changjiang Daily reporter Gao Yong
This test site built in a landslide is the Hubei Badong Geological Hazards National Field Scientific Observation and Research Station, "Badong Comprehensive Field Test Site Underground Tunnel Group" led by China University of Geosciences (Wuhan). Located on the Huangtupo landslide, the largest ancient landslide in the Three Gorges Reservoir area, it is also the world's only large-scale comprehensive field "underground laboratory" focusing on landslide disasters.
With it, four-dimensional three-dimensional observation of air, sky, ground and underground can be truly realized for geological disasters such as landslides; and the large difference between in-situ observation and laboratory data has also refreshed human understanding of landslides, the most important geological disaster. This is also the first time in the world that relevant data have been obtained through in-situ observation, effectively revealing the in-situ mechanical properties and structural characteristics of the slip zone soil, and providing important theoretical and data support for the prediction and forecasting of major landslides.
Li Changdong said that to understand how landslide disasters are caused, we must go into the disaster body. For the study of landslide hazards, it is very important and necessary to conduct in-situ sliding zone experiments in ancient landslides to obtain valuable first-hand data. However, for most engineering geologists around the world, it is indeed "conceivable but unthinkable". and". Relying on the observation conditions provided by the tunnel group, Tan Qinwen and others completed a number of complex experiments in the landslide and achieved a number of important scientific research results.
"In-situ observation is what we often call going out into the field. Going out into the field is the true nature of geologists. Our team members work in the field for long periods of time every year, drilling deep into mountains, climbing steep slopes, braving the scorching heat, and eating pickles," Li Changdong said, "Thanks to Tan Qinwen's My girlfriend also majors in geology, and she can understand it after being out in the field for half a year.”
Professor Li Changdong conducts rock mechanics tests on the MTS testing machine. Photo by Changjiang Daily reporter Gao Yong
Others can study it, China must study it
Geological disaster prediction has been a century-old problem. The geological structure is extremely complex, and the factors that cause geological disasters are diverse, so previous geological disaster predictions can only be based on history. Make a rough estimate based on experience.
However, "my country is the country with the most serious geological disasters in the world, and Hubei Province is one of the areas with the most frequent and intense geological disasters in my country." Tang Huiming told the story of his team, starting with cold data , "In the geological disaster reports released every year in my country, landslide disasters are the most important, accounting for more than 70%. Geological disasters in Hubei Province threaten a population of 660,000 and threaten property of 49.4 billion yuan. Nationwide, the data will be even greater."
Tang Huiming is the chief professor of geological engineering at China University of Geosciences (Wuhan). He has been involved in the evolution and process control of major landslides for more than 30 years. He is also the leader of the "Landslide Disaster Evolution Mechanism and Management" project team. Li Changdong and Tan Qinwen are both members of this team. Members. This large team of dozens of teachers and students covers talents from multiple disciplines such as engineering geology, hydrology, electromechanical, and computer science. They use cross-disciplinary integration to devote themselves to organized scientific research.
A heavy rain may trigger a large-scale scientific research. A landslide can annihilate a village or town; a mountain movement may also cause a landslide, block rivers, and destroy roads and railways... The most important thing to study geological disasters is to study landslides. For most countries in the world, landslides are just a geological disaster. ; For a few countries, landslides are an imminent geological disaster. China is one of these few countries. Others can study landslides, but China must study landslides.
"We have witnessed too many landslide disasters. As researchers, We are heartbroken and anxious. "Tang Huiming said that with the implementation of my country's major strategies, the contradiction between engineering activities and the geological environment has become increasingly prominent. "The prediction and prevention of landslide disasters are crucial and extremely urgent. "
In addition to being limited by technical means, it is difficult for humans to accurately predict and predict landslides. The reason is that the law of landslide occurrence and the mechanism of landslide formation have not been fully discovered. Starting from the most basic landslide mechanism, Tang Huiming asked everyone to start from the most basic landslide mechanism when he formed the team. Start with the difficult part. “This is a very difficult research, and we have encountered bottlenecks many times, but difficulties are always there, but I have never lost confidence. Our goal is very clear: don’t do it if you don’t want to, do it well if you do it, and be No. 1 in the world! "
In order to collect data, they made their own sensing unit chips, manufactured sensors and other monitoring tools, and independently developed a landslide multi-field correlation monitoring system, using modern scientific and technological means such as satellite remote sensing, drone photography, and multiple sensor monitoring. Three-dimensional tracking of multi-field evolution characteristic data of landslides.
“Various data are clear at a glance. "Li Changdong pointed to a laptop computer and said that the computer screen was constantly refreshing data from a monitoring system in Zhejiang. "You can also view it with your mobile phone. Once any data is abnormal, the machine will automatically mark it. "
With massive data , they set out to model, analyze the mechanism, and reclassify the occurrence mechanism of landslides. "There are many teams around the world studying landslide prediction, but the landslide prediction based on physical mechanics process Predictive research is our specialty and innovation, and the more fundamental it is, the more original it is. Facing the country’s major needs, we must strive to do our best to predict the landslide evolution process. "
They reclassified landslides into three categories based on the occurrence of the sliding process, and studied the corresponding mechanical mechanisms of landslides according to the mechanism research of each category. "Don't look at the simple classification, it means that our understanding of landslides has entered a new stage. A whole new level. "The full-fledged Tang Huiming was full of enthusiasm.
Professor Tang Huiming guided the rock mechanics test data processing. Photographed by Yangtze Daily reporter Gao Yong
The painstaking efforts of five generations
Li Changdong told a prediction story: more than ten years ago, they were working in Ba They did on-site monitoring of the high slope in the east and found that some data changes were very dramatic. From a mechanism perspective, the landslide entered a period of rapid development. They quickly contacted the local government and submitted an emergency plan, which was quickly adopted by the local government. The slope was reinforced and treated, and the landslide disaster was successfully avoided.
From predicting the occurrence of landslides to the fact that landslides did not occur, it is like a doctor treating a disease before it occurs, rather than verifying the disease. How accurate it is to prevent it from happening and eliminate the disaster invisibly. The earlier the forecast is made, the smaller the damage will be. " Li Changdong said.
Since the establishment of China University of Geosciences in 1952, the study of geological hazards has continued to this day. China University of Geosciences moved from Beijing to Wuhan, and this discipline was completely moved to Wuhan.Tang Huiming calculated on his fingers that landslide disaster research has been passed down for five generations, from his mentor, Professor Yan Tongzhen, the founder of geology at the University of Geosciences, to the young teachers and graduate students born in the 1980s and 1990s. For decades, from the data accumulated by the older generation’s long-term field observations to the comprehensive data collected by today’s high-end instruments, Tang Huiming said that the prediction and prevention of landslide disasters has been the desire and hard work of generations of people.
Tan Qinwen’s colleague Gong Wenping was born in 1989. He is currently a professor and doctoral supervisor in the School of Engineering, and a young backbone of the landslide geological hazard research team. He once obtained a doctorate in the United States in less than two and a half years and stayed at the school to teach. However, because he was determined to serve the country, he resolutely gave up the superior conditions overseas and returned to China full-time to devote himself to the motherland's geological disaster prevention and reduction and talent training.
"I live in the mountainous area of northeastern Sichuan. I have been exposed to the dangers of geological disasters since I was a child." The May 12 Wenchuan earthquake in 2008 triggered a large number of secondary geological disasters. The casualties and property losses shocked him even more. Decided to engage in geological disaster research. After
came to Jida, in order to obtain key on-site data on geological disasters, he overcame many difficulties, traveled over mountains and ridges, often ate and lived in the wild, and traveled to Hubei, Sichuan, Chongqing, Guizhou, Yunnan and other areas with high geological hazards in my country, and obtained A number of original scientific research achievements.
Like Gong Wenping, in the past ten years, the geological masters have been stationed in rotation for a long time, providing basic long-term observation data for the prevention and control of geological disasters, especially landslide disasters, in the Three Gorges Reservoir area. Today, their scientific research results have been widely used in large-scale national projects such as the Three Gorges Reservoir Area, Baihetan Hydropower Station, Sichuan-Tibet Railway, etc. "The national needs are our research direction." Gong Wenping said.
Associate researcher Zhang Yongquan demonstrated the independently developed landslide large deformation flexible inclinometer sensing unit. Photographed by Changjiang Daily reporter Gao Yong
(Changjiang Daily reporters Zhou Jie and Chen Xiaotong, correspondents Wei Haiyong and Wang Junfang)
[Editor: Zhao Ke]
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