Except for the wheel hubs, the other vehicle wreckage resembled mud-caked paper balls, almost beyond recognition.

5 Month 7 At 1:00 AM on S12 Meilong Expressway East Extension K11+900m These parts, retrieved from the landslide site, were laid by the roadside. The more intact frames were placed on an empty lot near the Meizhou Dapukou Transportation Management Bureau. Most of the accident vehicles were dented and deformed, with shattered glass. Mud and sand coated the remaining frames; some vehicles were missing engine compartments at the front, with clear burn marks; each vehicle had red paint number markings, from “1” to “23” 。

According to the press conference on the landslide rescue operation on the Chaoyang section of the Meida Expressway, as of 5 Month 2 Date 14 at 23 vehicles had fallen, with 48 deaths, and 3 people DNA samples are awaiting further comparison and confirmation; 30 people were injured, currently with no life-threatening conditions.

The Paper learned from informed sources that the landslide section had experienced water damage in 2022 Year 8 Month, with slope collapse and damage to the spillway. Reinforcement and drainage improvements were subsequently carried out. The repair project was completed in phases from 2023 Year 4 Month to 9 Month.

In addition, The Paper's investigation revealed that there had been multiple maintenance inspections in this section or surrounding areas before the incident. In the month prior to the landslide, at least 5 maintenance crews had worked on cleaning the drainage system within one kilometer of the landslide area; in the week prior to the landslide, they also backfilled and sealed a partially hollowed section of the secondary slope platform about 500 meters away, and felled trees, the closest being about thirty meters away. Maintenance personnel stated that approximately one hour before the landslide, they passed through the affected section and found no abnormalities on the road surface.

As the operator of the Meida Expressway, Guangdong Dachao Highway Co., Ltd. (hereinafter referred to as “ Dachao Company ” ”) listed 2024 key slopes on the Meida Expressway in 41 Year, including the landslide location at K11+870-K12+153 downhill embankment slope, and equipped with GNSS automatic monitoring equipment.

Chen Zhipeng, a scholar specializing in geotechnical engineering and slope stability analysis, told The Paper that special reinforcement is generally not carried out on mountain roads, “ a balance must be struck between safety and economy ” expressway design accounts for 50 Year, 100 Year once-in-a-century rainstorms and floods, but extreme weather can still exceed the capacity of the road.

Within the industry, patrol maintenance of slope embankments is constrained by funding, manpower, and technology. Even with intelligent slope displacement monitoring equipment, GNSS there may be monitoring blind spots. Li Jiachun, an associate professor at the Chang'an University School of Highway Engineering, pointed out to The Paper that if the landslide was sudden, GNSS the equipment might not have had time to issue a warning.

According to Xinhua News Agency 5 Month 4 Date report, after the landslide disaster, the Guangdong Provincial Government established a disaster investigation and assessment team headed by the governor, and the cause of the disaster is currently under investigation and assessment.

 

5 Month 1 Date, some roads in Sanhe Town, Dapukou County were closed due to safety concerns with the roadbed. The Paper reporter Renwu, photo

 

“ After about ten vehicles fell, a fire started. ”

Having survived the ordeal, 67 year-old Huang Jiandu watched smoke rise from the landslide site.

4 Month 30 On the evening of 7 Date, his son-in-law drove his family of

from Shenzhen Longgang back to their hometown in Meizhou. At around 2:30 AM the next day, while driving on a section of the Meida Expressway, everyone was asleep when the vehicle suddenly lurched, jolting them awake.

Huang Jiandu's granddaughter, Rao Xinyu, recalled that the roadside guardrail behind them was collapsing, the right tire got stuck in a crack in the road and blew out, but her father pressed hard on the accelerator, speeding up. The car swayed violently, narrowly avoiding hitting the guardrail, ultimately rushing past the suddenly collapsed road surface. 17.9 Photos from the scene show that the accident section is a four-lane highway, and the landslide started from the median strip. According to previous reports from Nanfang Daily, the length of the collapsed road section is approximately 184.3 meters, and the area is approximately

square meters. After rushing past the landslide for one or two hundred meters, Huang Jiandu's family quickly got out of the car and ran back, holding up flashlights to signal other cars to stop, but more vehicles still fell into the pit. “ In a moment of urgency, Huang Jiandu crawled under the guardrail next to him, ran from the opposite lane to the front of the landslide, and knelt down to stop the dozen or so vehicles that were about to proceed. He recalled to The Paper, ”

Multiple survivors of the landslide told The Paper that some vehicles were stacked on top of each other at the landslide site, accompanied by explosions. 5 Month 1 at dawn 2 o'clock 27 Screenshots from WeChat Moments shared at minutes show a large plume of smoke dyed red by the firelight under the night sky, “ The bridge is broken, many cars have fallen, continuous explosions. We were only 100 meters away from death. ”

37 -year-old Liu Yongjin and "00 Post ” retired soldier Cai Xuanda, chose to risk their lives to rescue others.

Liu Yongjin recalled that more than ten cars caught fire one after another, and people kept getting out of the cars, about three or four meters away from the fire. After discovering a gap in the roadside ditch, they climbed down along the railing, holding a mobile phone flashlight in one hand, and grabbing the weeds on the slope with the other to prevent slipping.

“ The vertical drop from the bottom to the roadbed was approximately 4 meters, but after walking for five or six minutes ” Liu Yongjin said that they walked "Z" shape little by little closer to the landslide site. It was pitch black, and they could only identify their location by the cries for help and the sparks from the burning vehicles. He heard four explosions; each time, cries for help from the crowd would echo from the bottom of the slope a few meters away.

The six injured people he helped rescue came from three accident vehicles. The youngest girl was only 3 years old. When Liu Yongjin handed her to Cai Xuanda, she coughed up several mouthfuls of blood on his shoulder; the girl's father, 30 years old, said that his ribs were broken, and he was climbing up with difficulty, grabbing the weeds. Liu Yongjin supported the man's buttocks to help him climb.

Liu Yongjin remembered that there was also a boy of about ten years old who kept clutching his left leg and shouting in pain, saying that his mother was still under the car and hoped that someone could save her. However, it was difficult to approach the accident vehicles, so he could only hold the boy under his armpits and lift him up to Cai Xuanda. As the flames were almost level with the road surface, the heat wave surged, and they didn't dare stay any longer.

A netizen claiming to be a family member of the victims 5 Month 4 said on a social media platform on 4 Month 30 that evening, his family of five were returning to Meizhou from Foshan, when they encountered a landslide while exiting the highway. When they fell into a pit about two stories high, there were already several cars at the bottom. His two-and-a-half-year-old son hit the windshield from the back seat, and everyone was unconscious. After carrying his son to a relatively safe pile of earth, he returned, but found that the rear door could not be opened. More cars fell and the fire began to spread; he could only carry his son and continue to climb. His wife, mother, and mother-in-law were engulfed by the fire, while his son was sent to the hospital due to cerebral hemorrhage. ICU for treatment.

A reporter from The Paper contacted someone close to this netizen, who said that the child has now been transferred to a general ward.

According to the plan, Zhang Wanwan's family and two friends planned a May Day self-driving trip to Xiamen. They drove two cars, with Zhang Wanwan, her husband, two children and her cousin in one car, and the two friends in another. After the landslide, Zhang Wanwan's family unfortunately fell to their deaths; the friends stopped at a rest area to use the toilet, and escaped the disaster. 5 Zhang Wanwan and her husband are both from Jiangxi Province and have been doing business in Guangzhou for many years. Their two children are in elementary school.

Some vehicles were missing their front engine compartments, showing clear burn marks.

 

Cover News
Picture   A person from Dachao Company said that there were

cameras on the section of road under its jurisdiction. Before the incident, the staff had just completed a routine monitoring patrol and found no abnormalities. After receiving a report of an accident from the traffic police department, they immediately checked the cameras on the accident site, but found that the network was down and the images could not be displayed. 1000 After the incident, the local government dispatched a total of emergency, public security, fire, health, transportation, and communication rescue teams with

personnel, and mobilized 577 rescue vehicles to carry out a carpet search and rescue after the incident. 64 On , the Meizhou Municipal Government held a press conference on the accident, stating that as of 2 pm that day, the accident resulted in

5 Month 2 deaths, and the identities of three others are 48 being verified. There were DNA vehicles that fell into the landslide. Most of them were buried in the soil at a great depth. Some vehicles also caught fire, which increased the difficulty of rescue. There had been heavy rainfall in the area, making the soil loose and difficult for large-scale rescue equipment to reach the core area for rescue. 23 On , the Meizhou City Heroic Deeds Appraisal Committee announced that it would confirm Huang Manqiu, Huang Jiandu, Wang Xiangnan, Liu Yongjin, Cai Xuanda, and

5 Month 10 others' heroic deeds of stopping vehicles and rescuing people during the Meida Expressway disaster. 5 The road section had undergone slope reinforcement last year.

 

Before the landslide, villager He Shenwei thought the highway slope

was acting as a “ flood control channel ” 。

The accident site is part of the Meizhou-Daping Expressway East Extension Line, passing through a mountainous area in Anqian Village, Chayang Town, Daping County, Meizhou City, and was completed and opened to traffic in 2014 Year 12 month. Last year, He Shenwei contracted the Anqian Village mountain pond reservoir to be used as a duck pond, which was located at the foot of the mountain below the landslide site, about 400 meters away in a straight line.

Since 4 month, Meizhou has experienced several rounds of heavy rainfall, with the average accumulated rainfall in the city being 621.7 millimeters, more than the same period of previous years 2.49 times, exceeding the historical meteorological records 4 the highest rainfall in history (1980 Year 437.3 millimeters ) 。From 4 Month 16 to 5 Month 1 consecutive 16 days of rain.

A person involved in the construction of the Mei-Da Expressway extension told The Paper that the section of road where the collapse occurred passed through the mountainous area, and was originally “ built by cutting into the mountain ” . In case of heavy rain, small-scale landslides often occurred on the rural roads of nearby villages.

With continuous rainfall, He Shenwei watched the water level of the duck pond rise continuously. The dirt road to the duck house was flooded, and even the excavator was useless, so he changed to a small boat to transport the feed. During this time, the duck pond became increasingly turbid in the rapidly accumulating drainage from the highway.

He recalled that 4 Month 28 in the morning, water gushed down the slope, “ whoosh ” for nearly an hour, mixed with a lot of sediment. When he 5 Month 1 received another notice from the village committee in the early morning, the duck house had been almost completely collapsed by the landslide, and the scene was cordoned off and inaccessible.

Public information shows that 2021 Year 1 Month 1 the operation and management of the Mei-Da Expressway was taken over by Da Chao Company, whose largest shareholder is Guangdong Communications Industry Investment Co., Ltd. ( hereinafter referred to as “ Guangdong Communications Investment Company ” ).

The Paper learned that the K11+870-K12+153 downhill embankment slope, including the location of the collapse, is one of the 2024 key slopes recorded by Da Chao Company 41 one of the key slopes recorded in the year, with sandy soil geological conditions. Arch-shaped frame grass-planting slope protection was used for slopes of levels one to three. The slope of the collapsed section was a diseased point eroded by rainwater, and had been repaired before the disaster.

2022 Year 8 In K11+870 to K12+153 section downhill slope (including the collapse location K11+900 ) showed signs of water damage, and commissioned the China Communications Second Highway Survey and Design Institute to carry out the treatment and repair project design.

According to the on-site survey, the secondary slope of the above-mentioned slope showed slope creep, cracking and deformation of the arch-shaped frame, and damage to the surface runoff channel.

At that time, the treatment plan was to reinforce and consolidate the slope surface, and the repaired slope surface used C20 concrete for slope protection; the surface runoff channel, platform interception ditch, and inspection steps were repaired; the interval between the slope foot and the slope surface drainage holes was increased to ensure effective drainage of slope water.

After the repair project plan was approved, from 2023 Year 4 Month to 9 Month.

In the view of Wang Lei, a bridge engineer engaged in the construction and maintenance of highways, the aforementioned slope water damage may be due to poor drainage, shallow ditches, or damage. Strong rainfall erosion and infiltration reduced the soil strength, increased the self-weight, and reduced the slope stability.

Chen Zhipeng, a scholar who studies geotechnical engineering and slope stability analysis, believes that from the perspective of geotechnical engineering theory, the aforementioned repair plan using concrete retaining walls can effectively maintain slope stability, but if the road drainage is not smooth, water pressure will be exerted on the soil, which may have side effects.

Chen Zhipeng said that mountain highway generally will not be specially reinforced unless the geotechnical conditions of the section are poor, and it is located in some special and important areas, such as residential areas, industrial areas or some important infrastructure near the bottom of the slope. There is no such situation around this collapsed section, and according to the geographical conditions of Meizhou, “ if every section is carefully done, the cost of the project will be too high, any engineering construction, safety and economy must be balanced. ”

“ Highway subgrade construction design will consider the frequency of heavy rain and floods, such as 50 once a year, 100 once in several years. If extremely bad weather is encountered, it may also exceed the carrying capacity. ” He said.

According to the press conference, by 5 Month 2 Da Chao Company has organized construction design units, maintenance design units, and slope experts to conduct on-site surveys and study repair plans for the damaged road sections.

The Paper contacted the company several times to understand the design, monitoring, and maintenance of the accident section, and the company said that they are cooperating with the investigation and have no more information to disclose.

At present, national and Guangdong provincial geological experts have rushed to the scene to conduct a field investigation of the disaster, evaluate the stability of the disaster body and its surrounding slopes, divide the safety area and danger area, and guide the establishment of a danger area 5 manual observation points and the deployment of 2 instrument and equipment observation points to conduct 24 hourly monitoring of the disaster body and its surrounding slopes.

 

The difficulties of highway subgrade maintenance monitoring

After the incident, maintenance personnel near the accident site rushed to the scene and began to set up roadblocks. Afterwards, firefighters arrived. Road maintenance workers are the closest to this highway on a daily basis, but even after the incident, they were surprised by the disaster.

The bidding information publicized by Da Chao Company shows that 2023 Guangdong Guanyu Highway Bridge Co., Ltd., Guangdong Lului Highway Co., Ltd., Guangdong Xin Yue Transportation Investment Co., Ltd., and Guangdong Jingtong Highway Engineering Construction Group Co., Ltd. have participated in the management of Da Chao Company S11 Dachao Expressway and S12 Meida Expressway daily maintenance.

Many Meida Expressway maintenance personnel stated that their daily work includes, but is not limited to, inspecting and repairing road guardrails, signs, pavement cracks, potholes, drainage ditches, and slopes.

One maintenance worker said that his maintenance team, 3 The key work since last month has been to clean up the expressway drainage system, and in 4 month, with continuous rain, the cleaning and inspection work has increased, and the number of maintenance personnel and shift arrangements have also increased.

From 3 month to 4 end of the month, at least 5 batches of maintenance personnel have been in the accident area 1 kilometers before and after carrying out drainage system cleaning, slope investigation, roadside weeding, sapling planting and other maintenance work.

Among them, 4 Month 25 On the day, maintenance personnel backfilled and sealed the local excavation of the secondary slope platform at a distance of 500 meters from the collapse point; 4 Month 27 On the day, maintenance personnel cut down the fallen tree at a distance of 30 meters from the collapse point.

A maintenance worker recalled to The Paper that at around 4:30 pm the day before the incident, he drove past the collapsed section and found no abnormal conditions such as stagnant water or cracks; less than an hour before the incident, other staff also drove through the section without noticing any obvious abnormalities.

After the accident, maintenance worker Zhou Shicheng and his colleagues rushed to the scene, and after clearing the weeds and shrubs on the slope, the crack and slope deformation were exposed, and even some drainage pipes were overgrown with weeds. He remembers one particularly serious location —— The retaining wall could not drain water, and the maintenance workers drilled holes about 20 meters deep, and there was still water flowing.

In Chen Zhipeng's view, if the workers did not find any cracks in the road surface before the collapse, it is also possible that the road surface and the underlying soil foundation have split. He explained that 4 Since the month, Meizhou has experienced continuous heavy rainfall, which may cause “ The water pressure is too high, and the groundwater is not discharged in time ” When the fissure water stored in the mountain increases, the pore water pressure between the road surface and the subgrade also increases, eventually pushing the subgrade outward “ push ” down.

Unlike what is reported in the media “ road surface collapse ” Chen Zhipeng believes that this Meida Expressway disaster should be described as “ subgrade slope collapse ”。

Subgrade refers to an earthwork structure formed by excavation or filling. According to Chen Zhipeng's analysis, when constructing a highway on such a hillside, the inner part is usually excavated, and the outer part is filled to form a plane. The initial location of this damage is located in the median strip of the highway, which is also the interface of excavation and filling.

Inspecting and maintaining slope subgrades is part of road maintenance, but due to limitations in funding, manpower, and technology, subgrade problems may be overlooked in actual maintenance.

Bridge inspection engineer Zhang Yue told The Paper that due to cost pressures, subgrade inspection mostly relies on manual labor, but this is difficult to cover some steep slopes with lush vegetation.

If drones are to be used, Zhang Yue mentioned that this not only requires approval, but also requires prior AI recognition training, and the cost may exceed the budget. He believes that in an ideal state, using satellite screening technology to screen subgrade hidden dangers is more efficient.

“ Dachao Expressway ” In 3 Month 29 day's official account article, it mentioned that in order to fully launch the pre-flood slope safety risk investigation and hidden danger management, the company mobilized “ manual inspection combined with drones ” using “ Beidou intelligent monitoring data assessment ”， “ investigation personnel dispatched 200 person-times, equipped with drones 5 sets, investigating high slopes 130 places ”。

Regarding whether the Hualu Company and the local natural resources bureau received any warnings before the incident, The Paper contacted the relevant departments but did not receive a reply.

Road and bridge engineer Wang Lei pointed out that even with instrument monitoring, if the route is too long, it is difficult to monitor all subgrades.

In addition, Li Jiachun mentioned in an interview with The Paper that collapses can be slow or sudden, and only the former can be GNSS issue a warning. However, if this disaster is more due to a rapid increase in soil moisture content, monitoring groundwater levels or water pressure may be more effective.

Regarding the prevention of rainwater infiltration into the soil, Zhai Qian, an associate professor at the School of Civil Engineering, Southeast University, introduced the capillary barrier system that has been promoted and applied in Singapore. This system can effectively block rainwater infiltration while not affecting the daily evaporation of moisture in the soil. “ The capillary barrier system is mainly divided into three layers: the first layer is the greening layer, where green plants can be planted; the second layer is the fine particle layer, mainly used as the drainage layer; and the third layer is the coarse particle layer, mainly used as the waterproof layer. ”

Chen Zhipeng said that this accident serves as a reminder that the prevention and control level of slope engineering geological disasters needs to be improved. He told The Paper that in order to prevent similar collapses of mountain highway, engineering design and maintenance should be equipped with engineers with expertise in geotechnical engineering; however, the status of geotechnical engineers in China is currently not high, they encounter price reductions during bidding, and work plans are difficult to be thorough. Once problems are found during work, road repair costs and traffic efficiency may become constraints.

After the accident, 5 Month 4 On the day, Guangdong Provincial Department of Natural Resources held a province-wide video dispatch meeting, requiring the rapid organization and implementation of a large-scale investigation of geological disaster risks and hidden dangers, focusing on “ mountainside, riverside, and village edge ” junctions, areas near mountains, cliffs, and slopes that are prone to disasters, and key areas such as completed or under-construction geological disaster control projects, to carry out “ a comprehensive ” investigation. Upon discovery of any risks or hidden dangers, immediate control measures must be implemented to minimize all types of risks. Strengthen geological disaster meteorological forecasting, early warning, and analysis and judgment of data from monitoring points, and promptly issue early warning information. The safety of the people must be prioritized, and arrangements for personnel evacuation and safety must be made.

(To protect the privacy of those interviewed, Hu Juntao, Zhang Wanwan, Chen Zhipeng, Wang Lei, Zhou Shicheng, and Zhang Yue are pseudonyms.)

The Paper reporters Ren Wu Chen Lei Liu Yuxiu Interns Lin Mingqin Zhong Chen Zhang Yuxin Yang Chunxi

（ The article originates from The Paper. This article was uploaded and published by The Paper. This article is a reprint and is only used for learning and exchange. The copyright belongs to the original author and the original publishing media. Infringement will be deleted）