Physicist and astronomer Stefan Feeney of University College London, one of the...
About 8,000 people die each year as a result of landslides. Saving a person during this natural disaster largely depends on the degree of awareness of the upcoming landslide and the level of awareness about the causes of its occurrence.
To increase your chances of survival, it is important to do the following:
Action algorithm
Always stay vigilant
1. Know the "enemy" by sight. Landslides occur when a layer of earth, interspersed with rocks, thickets, and some water, slides down sloping terrain. A landslide can vary in size and speed and is usually associated with earthquakes, volcanic eruptions and fires. Sometimes a landslide can be caused by human intervention in the natural landscape.
Landslides happen when water quickly soaks into the soil during a rainstorm or sudden snowmelt, turning the ground into a stream of mud that looks like cement or clay;
Having different speeds, landslides can move over distances of up to several kilometers, capturing everything that comes their way, like an avalanche.
2. Constantly monitor the landscape around you. Find out if the area you live in or where you intend to travel belongs to a potentially hazardous area. I point out the following facts to the possibility of a landslide:
Change in the habitual appearance of the nearby territory (small shifts in the soil, progressive drying of vegetation, especially trees, incomprehensible shifts in the layers of the drainage system, etc.);
Doors and windows began to jam / loosely close;
Cracks in plaster, tiles or foundations;
The walls and threshold of the house are sloping;
Growing cracks appeared on the paths or roads near the house;
Underground communications broke down;
Soil protrusions appeared on the slopes;
Water seeps in unusual places;
Moved fences, trees, etc.;
Stepping on a slope, you feel how it moves;
The sound of breaking wood, the characteristic sound of a stream of water, or rattling stones may indicate the beginning of a landslide;
The growing roar indicates the approach of a landslide;
3. stay alert. If you notice any of the above, respond immediately. Listen to the forecast and news. Perhaps there will be a landslide warning.
4. Take care of the evacuation in advance. Think of the shortest and safest route that will take you to the safe zone.
First of all, think about those who may have difficulty moving quickly.
During a landslide
1. If for any reason you stay at home or you cannot evacuate, locate yourself on the second floor or attic of the house if possible.
2.If there is a stream or canal near your house, carefully observe the level and composition of the water in it. A sharp rise and turbidity of the water indicates the onset of a landslide. Don't delay evacuation! Save yourself first, not your property.
3. Be careful if you are evacuating by car. Keep an eye on the road and sidewalks for soil collapses, whether it is covered with stones or debris.
The flow of mud can blow the car off the track, overturn or damage it.
4. In whatever part of the evacuation you are caught by mud flows, as quickly as possible try to change direction. If this is not possible, curl into a ball and hide your head with your hands. Well, if there is a helmet nearby.
After the landslide
Even if the collapse is over, do not relax. In order not to fall victim to its consequences or not to fall into the epicenter of a new landslide, it is important to do everything possible to minimize the risk.
1. Do not approach the place where the landslide occurred. The danger of a second shift of the soil has not yet passed.
Follow the safety rules
2. look around whether there are injured people nearby. Send rescue teams to them.
3. be careful with nearby power lines, water supply or gas pipes. They may be defective and may cause harm. Carefully check the integrity of sidewalks, roads and bridges on which you have to move.
4. Be carefull when returning to your home:
It should be noted that after natural disaster it will be extremely difficult to do both physically and psychologically;
Use a battery-operated flashlight when inspecting the house. Turn it on before entering the room so that a working battery does not provoke a gas fire if it leaks;
When passing through rubble and flooded areas, beware of animals hiding there, especially snakes;
Do not use the phone unnecessarily, so as not to overload the line;
5. You should not go inside the house if:
You smell smoke;
Water has accumulated near the house.
The local authorities have issued an opinion that your home is unsafe.
6. Make changes around your home. To avoid a landslide, you can:
Restoring the ground cover at the site of the landslide. This will help to avoid erosion and prevent the recurrence of a landslide;
Make an expert geological assessment of the area in order to develop a number of corrective and preventive measures.
Learn information about possible locations and approximate boundaries of landslides, remember the warning signals about the threat of a landslide, as well as the procedure for issuing this signal. Signs of an impending landslide are jamming of doors and windows of buildings, seepage of water on landslide-prone slopes. If there are signs of an approaching landslide, report it to the nearest post of the landslide station, wait for information from there, and act according to the situation yourself.
How to deal with a landslide
When receiving signals of the threat of a landslide, turn off electrical appliances, gas appliances and water supply, prepare for immediate evacuation according to pre-developed plans. Depending on the landslide displacement speed detected by the landslide station, act according to the threat. With a low displacement rate (meters per month), act according to your capabilities (move buildings to a predetermined place, take out furniture, things, etc.). If the landslide displacement speed is more than 0.5-1.0 m per day, evacuate in accordance with previously developed plans. When evacuating, take documents, valuables with you, and, depending on the situation and instructions from the administration, warm clothes and food. Urgently evacuate to a safe place and, if necessary, help the rescuers in digging, extracting victims from the collapse and rendering assistance to them.
Actions after the displacement of the landslide
After the displacement of the landslide in the surviving buildings and structures, the condition of the walls, ceilings is checked, damage to the lines of electricity, gas, and water supply is revealed. If you were not injured, then, together with the rescuers, remove the injured from the rubble and provide assistance to them.
Hurricane, storm, tornado
Hurricane - this is a large atmospheric vortex with a wind speed of up to 120 km/h, and in the surface layer - up to 200 km/h. Storm - a long, very strong wind with a speed of more than 20 m/s, usually observed during the passage of a cyclone and is accompanied by strong waves at sea and destruction on land. Tornado - an atmospheric vortex that arises in a thundercloud and spreads down, often to the very surface of the Earth in the form of a dark cloud sleeve or trunk with a diameter of tens and hundreds of meters. It does not exist for long, moving with the cloud. Danger for people with such natural phenomena consists in the destruction of road and bridge surfaces, structures, overhead power lines and communications, ground pipelines, as well as the defeat of people by fragments of destroyed structures, glass fragments flying at high speed. In addition, people can die and be injured in the event of a complete collapse of buildings. During snow and dust storms, snow drifts and accumulations of dust ("black storms") on fields, roads and settlements, as well as water pollution, are dangerous. The main signs of the occurrence of hurricanes, storms and tornadoes are: increased wind speed and a sharp drop in atmospheric pressure; heavy rainfall and storm surge; heavy snowfall and ground dust. If you live in an area prone to hurricanes, storms and tornadoes (Far Eastern, Central and other economic regions Russian Federation), see:
Warning signals about an approaching natural disaster; - ways to protect people and increase the stability of buildings (structures) to the effects of hurricane winds and storm surge of water; -rules of human behavior in the event of hurricanes, snow and sand storms, tornadoes; - ways and means of eliminating the consequences of hurricanes, tornadoes, storm surge of water, snow and sand storms, as well as methods of providing assistance to victims who find themselves in the rubble of destroyed buildings and structures; - places of shelter in the nearest basements, shelters or the most durable and stable buildings of your family members, relatives and neighbors; - exit routes and accommodation areas during organized evacuation from high-risk areas; -addresses and phone numbers of the civil defense and emergency department, the administration and the commission for emergency situations of your locality.
After receiving a storm warning signal, proceed to:
Strengthening the roof, chimney and ventilation pipes; -sealing windows in attic spaces (shutters, boards or plywood panels); - release of balconies and the territory of the yard from fire hazardous objects; -to collect supplies of food and water for 2-3 days for evacuation to a safe area, as well as autonomous lighting sources (lanterns, kerosene lamps, candles); - move from light buildings to more durable buildings or to civil defense defenses.
Landslide control methods are established on the basis of a thorough study of natural physical and geological conditions, an understanding of the main causes of instability and analytical calculations of the limit equilibrium of the soil masses under consideration. In practice, the following are used as the main anti-landslide measures:
- organization of the runoff surface water in the zone of landslides and territories adjacent to it;
- drainage groundwater by constructing various drainage systems;
- reduction of external loads;
- · flattening of slopes and their loading with the help of counter-banquets;
- fencing of slopes and their protection from undermining and erosion flowing waters rivers or waves of the seas, reservoirs;
- · green spaces along the top of the slope and landslide slope;
- · artificial fixation of the masses of the landslide body;
- · artificial constructions to hold the ground masses.
Such activities are carried out:
- · via vertical layout and production of earthworks;
- through the installation of drainage networks;
- application of agroforestry measures;
- With the use of retaining walls, breakwaters, piles, etc.
With the help of vertical planning and earthworks, slopes are laid and counter-banquets are created. Slope flattening aims to reduce the steepness of the landslide slope, which ensures its stability. Flattening the slope is expedient as a preventive measure in the presence of an inactivated landslide. In addition, the expediency of slope flattening is determined by the volume of earthworks and the nature of the soil (Fig. 2).
Thus, due to the counter-banquet, the weight of the body of the landslide in its lower part increases and a certain stop is created that counteracts the sliding mass of the landslide.
collapse landslide rock formation
Rice. 2. Schemes of options that restrain the movement of the lower part of the landslide: 1 - persistent prism; 2 -- landslide body; 3 -- sliding surface; 4 - the original surface of the slope; 5 - drainage; 6 -- drainage tray; 7-- piles; 8 -- reinforced concrete box
Groundwater drainage is also one of the main landslide control measures. For this, various drainage systems and types of drainage are used, which allow full or partial interception of the ground flow.
There are two types of landslide slope drainage: head drainage, which intercepts the ground flow above the landslide slope, and slope drainage, designed to drain the body of the landslide itself.
The most significant is the drainage laid along the upper edge of the slope and intercepting groundwater, preventing their exit to the landslide slope. to a decrease in filtration pressure, which affects the stability of the slope.
As head drainage systems, horizontal single-line or two-line drainages are used: tubular - with an aquifer depth of 2-3 m; solid slots (slots) - open with a depth of 3--4 m and closed - with a depth of up to 10--12 m drainage galleries laid open way and adits built in a closed way, in or below aquifer.
Pile-type structures are used when the installation of persistent structures is impractical for planning or other reasons. In practice, wooden, concrete and reinforced concrete, and sometimes metal piles are used. The number of piles is determined by the load on the pile, calculating the overturning and shear. In order to avoid slope shaking during pile driving, holes are pre-drilled for each pile with a diameter slightly less than its calculated one.
Piles are located in the plan in checkerboard pattern and buried in non-moving soil to a depth of at least 2 m.
Thus, all these measures are expensive and time-consuming to perform, therefore, they are applied on the basis of a thorough analysis of the reasons for the development of the shift process, and the choice is made on the basis of a technical and economic comparison of options.
Rice. 3. Scheme of lowering the level of groundwater in the landslide section of the slope with a closed drain: 1 - level ground water before the construction of the drainage; 2 - drain; 3 -- depression curve; 4 -- backfilling the trench with compaction
Rice. 4. Groundwater interception schemes (slope drainage): a - adit with vertical drains; b - adit with driven filters; 1 -- landslide body; 2-- aquifers; 3-- bedrock; 4 - adit; 5-- drainage well; 6-- plug filter; 7-- groundwater level; 8-- depression curve
Rice. 5. Schemes of pile rows used to hold a landslide a - pile field; b -- supporting wall on piles; 1 - bedrock; 2 sliding plane; 3 piles; 4 surface natural relief; 5 - filtration backfill; 6-- retaining wall; 7-- water outlet
Landslide forecasting
For a more accurate prediction of landslides, it is necessary: mass analysis rocks, analysis of the conditions of already known and past landslides. Experience and specialized knowledge. Carrying out complex protective engineering works, they are active measures to protect against landslides. Slope planning, leveling of hillocks, sealing cracks in slopes. Implementation of planned and strictly dosed explosions in landslide hazardous areas Construction of tunnels and covered fences, as well as protective walls along the route of the railway. and highways Reducing the steepness of the slope with the help of machinery or directed explosions. Construction of roads, flyovers, viaducts. construction retaining walls, construction of rows of piles. The device of the guide walls. Groundwater interception drainage system(system of special pipes), regulation of surface runoff with patches and cuvettes. Protection of slopes by sowing grasses, trees and shrubs. Transfer of power lines, oil and gas pipelines and other facilities to safe areas. Protection of slopes, road, road and railway embankments by concreting and landscaping. Training of people living, working and vacationing in dangerous areas. Compliance safe mode, building codes and regulations, as well as instructions and standards.
Carrying out all the above conditions by professionals.
Landslide protection measures
The population living in landslide-prone areas should know the sources, possible directions and characteristics of this dangerous phenomenon. Based on the forecast data, residents are informed in advance about the danger and measures regarding the identified landslide sources and possible zones of their action, as well as the procedure for signaling the threat of this dangerous phenomenon. Also, earlier informing people reduces the impact of stress and panic that can arise later when emergency information about the imminent threat of a landslide is transmitted.
The population of dangerous areas is also obliged to carry out measures to strengthen the houses and territories on which they are built, as well as to participate in the construction of protective hydraulic and other engineering structures. The notification of the population is carried out with the help of sirens, radio, television, as well as local warning systems.
If there is a threat of a landslide and if there is time, an early evacuation of the population, farm animals and property to safe areas is organized. Valuable property that cannot be taken with you should be protected from moisture and dirt. Doors and windows, ventilation and other openings are tightly closed. Electricity, gas, water are turned off. Flammable, poisonous and other dangerous substances are removed from the house and buried in pits or cellars as soon as possible. In all other respects, citizens act in accordance with the procedure established for organized evacuation.
When there is a threat of a natural disaster, residents, taking care of their property, make an emergency independent exit to a safe place. At the same time, neighbors, all people on the way should be warned about the danger. For an emergency exit, it is necessary to know the routes to the nearest safe places (mountain slopes, hills that are not prone to landslides).
In the case when people, buildings and other structures find themselves on the surface of a moving landslide area, one should, after leaving the room, move as far as possible upwards, acting according to the situation, beware of blocks, stones, debris, structures, and an earthen rampart rolling down from the back of the landslide , scree7.
After the end of the landslide, people who hastily left the disaster zone and waited for it in a nearby safe place should, after making sure that there is no second threat, return to this zone in order to search for and provide assistance to the victims.
The consequences of landslides
Landslides can destroy homes and endanger entire communities. They threaten agricultural land, destroy it and make it difficult to cultivate, create a danger in the operation of quarries and the extraction of minerals. Landslides damage communications, tunnels, pipelines, telephone and electrical networks; threaten water facilities, mainly dams. In addition, they can block the valley, form temporary lakes and contribute to flooding, as well as generate destructive waves in lakes and bays, underwater landslides tear telephone cables. As a result of landslides, riverbeds and roads can be blocked, and the landscape changes. Landslides threaten the safety of road and railway transport. Destroy and damage bridge supports, rails, road surfaces, oil pipelines, hydroelectric power plants, mines and others industrial enterprises, mountain villages. arable land located below the landslide areas are often waterlogged. At the same time, there is a loss of crops and an intensive process of land withdrawal from agricultural circulation8.
Significant damage by these phenomena can be caused to the cultural and historical heritage of peoples, the state of mind of people inhabiting mountainous areas.
Landslides mainly occur in areas of living tectonics, where the processes of slow sliding of blocks interact and alternate. earth's crust along faults and rapid movements in earthquake sources.
Landslides in the Russian Federation take place in mountainous areas North Caucasus, Ural, Eastern Siberia, Primorye, about. Sakhalin, Kuril Islands, Kola Peninsula, as well as on the banks of large rivers.
Landslides often lead to large-scale disasters. For example: a landslide in 1963 in Italy with a volume of 240 million cubic meters. meters covered 5 cities, while killing 3 thousand people. In 1989, landslides in Checheno-Ingushetia caused damage in 82 settlements of 2518 houses, 44 schools, 4 kindergartens, 60 healthcare, cultural and consumer services.
With the threat of a collapse, landslide or mudflow (if there is time), the evacuation of the population to safe places is organized. Before leaving the house, the most valuable property is protected from dirt and moisture. Doors and windows are tightly closed. Electricity, gas, water are turned off. Documents, valuable and necessary things, money, a small supply of food, water, and medicines are taken with you.
If the residents were warned about the threat immediately before the onset of a natural disaster or noticed its approach themselves, each of them, not caring about property, makes an emergency independent exit to a safe place. Natural safe places for an emergency exit are the slopes of mountains and hills that are not located to the landslide process and are not located in a mudflow-prone direction. When climbing safe slopes, it is necessary to bypass valleys, gorges and recesses, since side channels of the main mudflow can form in them.
In the case when people, buildings or other structures are on the surface of a moving landslide area, it is necessary, after leaving the premises, to leave the danger zone, moving as far as possible upwards. After the end of a landslide, mudflow or collapse, people who left the disaster zone and waited it out in a safe place should make sure that there is no second threat and return to this zone to provide assistance to the victims, remembering that outside help will not come immediately to hard-to-reach mountainous areas.
snow avalanche- this is a snowfall, a mass of snow falling or sliding from the mountain slopes under the influence of some kind of influence and entraining new masses of snow on its way.
Avalanches form on treeless slopes with a steepness of more than 15°. Optimal conditions for the formation of avalanches are created on slopes with a steepness of 30-40 degrees. On such slopes, avalanches descend when the layer of freshly fallen snow is 30 cm, and for the formation of avalanches from old (stale) snow, a layer of snow of up to 70 cm is needed. At a steepness of more than 50 °, the snow crumbles to the foot of the slope, and avalanches do not have time to form. In order for the avalanche to start moving, the length of the open slope of the mountains should be 100-500 m. The speed of the avalanche can reach 100 m/s, and on average it is 20-30 m/s.
Depending on the condition of the snow, avalanches are either dry or wet. Dry avalanches are made up of freshly fallen snow. They are rapidly rushing from the mountains and crumble during movement. A dry avalanche forms an air wave that goes ahead of the snow bank, spreads hundreds of meters and poses a real threat to humans. Wet avalanches consist of stale snow and carry a lot of stones, earth, trees, branches.
The volume of the falling mass of snow often reaches 0.5-1.0 million m 3, and the impact force of the avalanche reaches 60-100 tons per 1 m 2.
Causes Avalanche formations can be divided into natural and anthropogenic.
To natural include: strong and prolonged blizzards, snowfalls; sudden thaws, wind blowing snow from the leeward layer and transferring it to the ridge, the formation of a cornice over the windward slope. One of the natural causes of avalanches are earthquakes.
to anthropogenic reasons include deforestation and bushes on slopes; violation of the grass cover by irregular grazing; imploding works; use of strong sound sources; even a loud cry.
Avalanches are extremely dangerous phenomenon threatening settlements, sports and health resort complexes, railways and roads, power lines and other facilities. To some extent, avalanches cause damage and agriculture, because they violate the integrity of the soil and vegetation cover, fill up mountain pastures with stones and tree roots. The secondary damaging factors of avalanches include the formation of dams on rivers. As a result of the formation of avalanche dams, water levels can rise by 5-7 m. As a result of snow melting and soil erosion, such dams collapse after a while, and the mass of water rushes down the river, causing mudflows.
There are many examples of catastrophic losses caused by snow avalanches. In particular, this one. During the First World War, more than 60 thousand soldiers died under avalanches on the Austro-Italian front in the mountains - this is more than directly in the battles. The saddest date of the entire military campaign was December 16, 1916. On this day, avalanches buried 6,000 soldiers.
Currently in Europe annually avalanches different kind take an average of 100 human lives. In Russia, avalanches take place in the Urals, the Kola Peninsula, in the south Western Siberia, in Eastern Siberia, on Far East and in the North Caucasus.
Avalanche protection can be passive or active. Passive methods of protection consist in the use of: dams, avalanche cutters, gouges, snow shields, planting and reforestation.
Active methods consist in artificially provoking an avalanche at a pre-selected time and subject to safety measures. For this purpose, the warheads of potential avalanche disruptions are fired with explosive projectiles or mines, directional explosions are organized, and strong sound sources are used. In places where avalanches pose a great threat, avalanche stations are formed, and with them - a service to save people.
The Art of Survival
Landslide and mudflow - what to do in emergency situations
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Mud flow is a temporary flow of a mixture of water and a large number fragments of rocks from clay particles to large stones and boulders, suddenly appearing in the channels of mountain rivers and hollows.
Mudflow is born after long and heavy rains, intensive melting of snow or glaciers, breakthrough of reservoirs, earthquakes and volcanic eruptions.
It arises suddenly, moves at high speed (up to 10 m/s or even more), and most often passes in several waves over a period of tens of minutes to several hours. The steep leading front of a mudflow wave can be up to 15 m or more high.
The rumble and roar of a moving mudflow can be heard in the mountains at great distances. People may be in distress (tourists, geologists, border guards, local residents), residential buildings, engineering and road constructions.
How to prepare for a village
Usually, the places where mudflows can go are known. Before going to the mountains, study these places on your route and avoid them, especially after heavy rains. Always remember that it is almost impossible to escape when caught in a mudflow. You can save yourself from a mudflow only by avoiding it.
Before leaving the house, in case of early evacuation, turn off electricity, gas and water supply. Close doors, windows and vents tightly.
Early action to prevent mudflows
In mudflow-prone areas, anti-mudflow dams and dams are being built, bypass channels are being built, the level of mountain lakes is lowering, the land on the slopes is being strengthened by planting trees, observations are being made, a warning system is being organized and evacuation is planned.
How to deal with mudflow
Hearing the noise of an approaching mudflow, you should immediately rise from the bottom of the hollow upstream, at least 50-100 m. At the same time, you need to remember that stones can be thrown out of the roaring stream for long distances heavy weight life threatening.
Actions after the mudflow
Provide assistance to the victims and assistance to the formations and bodies that disassemble blockages and drifts along the path of the mudflow and in places where the main mass of the mudflow is removed. If you are injured, try to get yourself first aid. The affected areas of your body, if possible, should be kept in an elevated position, put on them ice (wet matter), a pressure bandage. Contact your doctor.
Landslide
A landslide is a sliding displacement (sliding) of masses of soil and rocks down the slopes of mountains and ravines, steep coasts of seas, lakes and rivers under the influence of gravity.
The causes of a landslide are most often the erosion of the slope, its waterlogging by heavy rainfall, earthquakes or human activity (blasting, etc.). The volume of soil during a landslide can reach tens and hundreds of thousands cubic meters, and in some cases even more.
The displacement speed of a landslide ranges from several meters per year to several meters per second. Top speed displacement of a landslide is observed during an earthquake. The sliding of soil masses can cause destruction and blockages of residential and industrial buildings, engineering and road structures, main pipelines and power lines, as well as damage and death of people.
Landslide Prevention
Learn information about possible locations and approximate boundaries of landslides, remember the warning signals about the threat of a landslide, as well as the procedure for issuing this signal. Signs of an impending landslide are jamming of doors and windows of buildings, seepage of water on landslide-prone slopes. If there are signs of an approaching landslide, report it to the nearest post of the landslide station, wait for information from there, and act according to the situation yourself.
How to deal with a landslide
When receiving signals of the threat of a landslide, turn off electrical appliances, gas appliances and water supply, prepare for immediate evacuation according to pre-developed plans. Depending on the landslide displacement speed detected by the landslide station, act according to the threat. With a low displacement rate (meters per month), act according to your capabilities (move buildings to a predetermined place, take out furniture, things, etc.).
If the landslide displacement speed is more than 0.5-1.0 m per day, evacuate in accordance with a previously worked out plan. When evacuating, take documents, valuables with you, and, depending on the situation and instructions from the administration, warm clothes and food. Urgently evacuate to a safe place and, if necessary, help the rescuers in digging, extracting victims from the collapse and rendering assistance to them.
Actions after the displacement of the landslide
After the displacement of the landslide in the surviving buildings and structures, the condition of the walls, ceilings is checked, damage to the lines of electricity, gas, and water supply is revealed. If you were not injured, then, together with the rescuers, remove the injured from the rubble and provide assistance to them.
I will add from myself. This is a very complex topic. scientific work, often associated with underground streams and rivers, including hidden, invisible, seasonal and drying up. Specially labeled images and photographs of mudflows, processed on a modern PC computer - on the site about stones and minerals (deposits).
Material about water sources and mudflows:
