The main risk factors for the development of the seismic situation associated with earthquakes are concussion, liquefaction, layer-by-layer displacement of the soil, landslides, mudflows, avalanches, and slope of surfaces. As well as rock shear along the fault, tsunamis, standing waves, floods and fires.
Hazards associated with earthquakes, preparatory measures for earthquakes, actions during and after the earthquake.
The key threat to human life is not the earthquake itself, but its consequence. Shaking all that stands on it. Due to soil vibrations, the upper soil layers are disturbed. The foundation on which the buildings stand becomes unstable, with natural consequences.
Sometimes earthquakes lead to catastrophic floods. More often it is a tsunami (if a cataclysm occurred at the bottom of the ocean), which cause a huge number of victims. In this sense, they are usually more dangerous than the earthquake itself..
, which occurred at the beginning of the 20th century, for example, in Kanto, Japan, in modern cities are unlikely. The bottom line is the use of new materials in construction, the use of technologies that make buildings less vulnerable to fire, better organization and provision of fire services. And also in better work of the water supply system.
The probability that people will be at home at the time of the earthquake exceeds 60%. It is wonderful if, from the point of view of strength and stability of structures, structures meet the necessary requirements or have a wooden frame. Unfortunately, in practice this condition is far from everywhere. In many places on Earth, structures are traditionally being erected that do not withstand seismic criticism..
This, for example, the Asian region, the Mediterranean, South and Central America. Dwellings are often found here, the construction of which is carried out in the old fashioned way. And therefore, all conditions are created for mass death even during medium-intensity earthquakes. The reason for this situation is that many countries in these regions are rather poor and do not have sufficient economic resources to build earthquake-resistant buildings in rural areas in a short time..
Earthquake Hazard Reduction.
To significantly minimize damage during an earthquake, it is recommended that owners of buildings located in the seismic risk zone adhere to the basic requirements of earthquake-resistant construction and, if a finished construction is provided for housing, introduce certain improvements.
For external cladding, use waterproof plywood with a thickness of 10 mm or more. Moreover, attach it to the walls as carefully as possible. Since garage doors and wide windows affect structural rigidity for the worse, use additional fasteners.
The electrical equipment located inside the house (lamps, water heaters, refrigerators, stoves) is firmly fixed so that it can withstand any fluctuations in the soil.
In a home brick chimney, it is high-quality to close up the fittings and fix it so that there is no threat of collapse in the residential part of the house. In the absence of chimney reinforcement, the exhaust pipes should be lightweight. In areas of high seismic risk, reinforcement with four vertical steel bars is not enough to protect.
Some earthquake survivors advise first of all to find a place next to a large bulky object during earthquakes. If anything falls on it, then a cavity will remain in the neighborhood. For example, you can lie next to:
Large cabinet, etc..
And the baby’s pose will be the best, allowing to save space as much as possible..
The frame of the wooden house and the lower bars should be regularly inspected for damage from microorganisms or decay. Wooden elements must reliably provide resistance to lateral loads and communication with the concrete foundation.
Walls made of concrete blocks during earthquakes are prone to collapse. Therefore, they must be carefully associated with quality supports. Make roofs and ceilings as light as possible in local climates..
If in a particular zone of increased seismic hazard the soils of the base are mobile, it is necessary to think through and make flexible connections between the internal and main pipelines in advance.
Reinforcing furniture before earthquakes.
Cabinets hanging on the walls and any heavy furniture must be firmly fixed or tied to wall racks.
It is better to take care in advance of the additional strengthening of the hanging cabinets and other things, the reliability of the latches on the doors, the placement of dishes on the shelves. Such measures are able to repeatedly reduce possible losses..
On top of cabinets, as well as hanging shelves, it is worth nailing restrictive trims or other fasteners. To strengthen works of art that are undesirable to move, you can use small loops of transparent adhesive tape.
How to survive an earthquake.
First of all, it must be said that in an extreme situation, the main enemy of a person is inside himself – this is panic. By all means you need to maintain control over yourself and thus over the situation. This will help knowledge of how an earthquake occurs, what accompanies it and how to behave when tremors.
An earthquake is felt as strong ground vibrations, which usually last no more than a minute. From the first to the most powerful shocks, an average of 15-20 seconds pass, after which they decay sharply. In this short period of time, in order not to become a victim of a disaster, dedication, the ability to think soberly and the speed of reaction are extremely important.
Oscillations of the soil during an earthquake in themselves are practically not dangerous. However, they contribute to the fall of objects, stones, glass, walls, etc. .. Which leads to numerous victims..
The main risk factors associated with earthquakes.
Collapse of individual parts of the structure: bricks, chimneys, decorative elements of the exterior and interior, balconies, frames, lighting structures, statues.
Falling broken glass. Especially dangerous in the case of multi-story buildings.
Power line breaks.
Heavy objects falling indoors.
The occurrence of fires due to gas leakage from damaged pipes and short circuits of electrical networks. The threat of fires increases in the event of damage to the water supply and lack of water.
The onset of panic, due to which people are able to behave inappropriately, threatening others with their uncontrolled behavior.
The likelihood of becoming a victim of an earthquake will decrease if you first carry out all the necessary preparatory measures and think through your actions..
Preliminary actions and preparations for earthquakes.
Pre-planned behavior before earthquakes contributes to faster and more informed actions. However, you must be prepared to adjust your plans to suit the circumstances. Intense buildup and sudden shocks can cause the building to collapse. Slabs or elements of capital walls will fall.
In this situation, an attempt to run outside during a cataclysm seems less risky than staying inside. Moreover, it should be borne in mind that when collapse of non-capital walls and curtain wall panels, the talk about the destruction of the building may not go.
The plan of action before earthquakes should include the possibility of being in any place that you visit often enough: home, work, cinema, street. With the division into categories, it is easier to remember what needs to be done in specific situations before earthquakes. After all, the behavior in different places will be slightly different.
Order and responsibility are the main factors for successful preparation for earthquakes. Corridors, walkways, stairwells and internal doors must be emptied and heavy furniture securely attached to the walls..
Find out and remember the location of all:
Fire and gas cranes.
First Aid Kit.
The more family members know where that is and can provide first aid, shut off water and gas, turn off electricity, the better. Do not put beds near windows, and leave heavy objects on shelves. The house must have a battery-powered radio and a flashlight. In addition, it is necessary to discuss with family members in advance where there will be a meeting place.
Parents are required to get the leadership of the school in which their children are studying to give due consideration to the discussion of safety measures during earthquakes. At the workplace, you should also find out if there is an emergency plan for earthquakes, whether you have personal responsibility in case of emergency and, if so, what actions does it imply.
Visible signs of impending natural disaster:
The presence of gas odor where it had not been noticed before.
Anxious Animal Behavior.
Flashes in the sky, like the scattered light of lightning.
Sparking of adjacent but non-contacting electrical wires.
Pale blue glow inside houses.
A warning before earthquakes can be a signal of civil defense – the horn of a siren. If such a sound is heard, you need to turn on the receiver or TV, tune in to the local station and act in accordance with the information received.
If during an earthquake (even a strong one) you find yourself in a rural area, in the open part of the city or in a car on an open road, then everything will end happily. In any case, you need to stop the car and wait for the end of the shocks in it. If it is a bus, the driver must stop and open the door. Although passengers are not recommended to leave the vehicle.
Oddly enough, it is safer to wait for an earthquake in the subway than on the surface. Rather, it would be safer if it were not for the habit of people to panic. Especially when the lights go out, and in the subway, most likely, this will happen, so you need to be prepared for such a turn of events.
If an earthquake catches you indoors or outdoors, do not rush to escape from there, as many get injured just when they are in a hurry to enter or leave the building. In this case, a lot of people wishing to leave the building will accumulate at the exit, there will be a crush, people will interfere with each other, which can lead to very disastrous consequences.
Here, of course, circumstances need to be taken into account. When you are on the 1st floor, you can quickly leave the room at least through the door, through the window. But on the 2nd floor and above, such a maneuver is hardly feasible. Therefore, instead of taking risks along the way, it is more expedient to quickly find a reliable shelter away from windows in the room.
You need to sit near the wall, which is closer to the center of the structure, at the support column.
Get up in the doorway, under the arch, hide under a sturdy table. They will protect against falling chandeliers, plaster, etc..
Leaving the apartment in a high-rise building, go down the stairs, not hoping for an elevator. On the street you need to go out into the open. Bypassing overhanging electrical wires, pipes and what is able to fall. You cannot return to the affected building even after a few hours, since it can fall apart from the aftershock (subsequent shocks of lesser force).
In any case, fire extinguishers should be located where they are easy to get. If the water supply system fails, then a small amount of water to extinguish minor fires, provide first aid or quench thirst can be obtained in flushing tanks, water heaters, bottles of drinks, etc. The lantern should be kept at hand, since electricity usually disappears very quickly.
If you manage to make time, it is advisable to turn off the electricity and gas. Since gas leaks often occur during earthquakes, candles, matches and lighters cannot be used. The radio must be turned on, because they can transmit the necessary instructions. Do not take a phone that is useful for sending messages of high priority.
Panic is considered a critical hazard in natural disasters. Naturally, before and during earthquakes, it will begin one way or another. If possible, it is necessary to strictly suppress the stampede in the doorway, not to allow desperate people to jump out the windows. Sometimes this is done even through the glass of closed windows. Children must be constantly monitored..
After waiting for the end of the main strong shocks, you immediately need to get out into the street and move as far away from buildings, poles, fences as possible to some deserted place. As soon as possible, proceed to the inspection of the rubble and provide all possible assistance to the victims. You need to act very carefully, mindful of the aftershocks.
Actions in the event of an earthquake.
If you fall into the rubble, first of all, you must not succumb to panic and not waste your energy on it. Without food, a person is able to live a long time (if there is an experience of starvation, then 40 days), but without water it is much less, but still enough for the rescuers to make out the blockage. The main thing is not to lose heart.
You should determine your location, the presence of nearby exit and other people, listen and shout. If a pipe passes nearby, it must be used in order to give a sign about yourself.
After the earthquake.
First of all, you need to check the condition of the water supply and gas pipelines, to make sure the presence or absence of electricity. In case of damage, the corresponding system should be turned off. A gas leak is detected by smell, but not by ignition of a match. In a gas leak room, immediately open windows and doors, go outside and inform the appropriate services.
Damaged buildings are not recommended. Including in order to pick up things. There is a danger, especially in the first hours, that repeated shocks will occur. The threat persists for two to three days after the first powerful shock. If instructions from authorized persons have been received by radio or in any other way, or contingency plans are available, follow them..
Residents of coastal areas should not approach the coast closer than a few hundred meters, otherwise you could fall victim to the tsunami. If the house is on the coast, it is necessary to leave it and move away as far as possible from the water. The fact is that huge waves can come many hours after the earthquake.
Visiting an area affected by the elements is permissible only with permission. Usually, the authorities impose a state of emergency in order to effectively deal with looters and robbers.