Landslides
01
Learn about landslides
What is a landslide
Landslide refers to the natural phenomenon that the soil or rock mass on the slope slides down the slope as a whole or scattered due to various reasons.
Causes of landslides
The formation of landslides is usually caused by a combination of factors, the main causes include the following:
Natural Factors:
1. Geological conditions: The rock and soil structure and properties of the mountain are important factors. If the mountain is composed of loose sand, silty soil, broken rock, etc., its stability is usually poor and it is prone to landslides.
2. Topography: Steep slopes, deep river valleys, convex slopes and other terrain conditions increase the gravitational potential energy and sliding force, making the mountain more prone to sliding.
3. Precipitation: A large amount of rainfall, heavy rain or continuous precipitation will saturate the rock and soil, increase its weight, and reduce the friction and shear strength inside the rock and soil, thus causing landslides.
4. Earthquake: The shaking generated by the earthquake will disrupt the balance of the mountain, loosen the rock and soil structure, and lead to the occurrence of landslides.
5. River erosion: The erosion and erosion of the foot of the mountain by the river can weaken the support of the mountain and increase the risk of landslides.
Human Factors:
1. Unreasonable engineering activities: such as excavating the foot of the slope, stacking on the slope, blasting, changing the stress distribution of the mountain during the construction of roads and buildings, etc., may destroy the stability of the mountain.
2. Vegetation destruction: Excessive deforestation and reclamation of wasteland lead to the reduction of vegetation, which loses the protection and reinforcement of the mountain, and increases the possibility of soil erosion and landslides.
3. Underground mining: Underground mining activities in mines can lead to the formation of underground cavities, causing ground subsidence and landslides.
A precursor to the occurrence of a landslide
1. Cracks on the surface of the hillside: Horizontal and longitudinal radial cracks appear on the surface of the mountain, and the cracks may gradually widen, lengthen, and increase in depth.
2. Uplift of the soil at the front edge of the slope: The soil at the foot of the slope may be uplifted, which is caused by the forward pushing of the landslide body.
3. Tilting of trees, power poles, etc. on the hillside: Trees or power poles that were originally standing upright begin to tilt, indicating that the mountain is moving.
4. Abnormal spring water and well water: The water quality becomes turbid due to the sudden discharge of spring water that was originally dry, or the water level of the well water suddenly rises or falls.
5. Abnormal noises from underground: Sometimes you can hear abnormal sounds such as muffled thunder and rock cracking coming from inside the mountain.
6. Abnormal animal behavior: Abnormal behaviors such as panic and restlessness and not falling asleep in poultry and livestock, and rats running around and not entering holes.
7. Slope deformation acceleration: The deformation rate of the hillside is accelerated, such as the rapid expansion of cracks and the continuous occurrence of small collapses.
8. Cracks at the back of the mountain: At the trailing edge of the landslide body, new cracks may appear and spread rapidly.
If any of these signs are found, report them to the relevant authorities immediately and evacuate the danger zone as soon as possible.
02
How to save yourself in a landslide
1. Stay calm: When it comes to landslides, panic can make you make bad decisions. Try to calm yourself down and judge the situation quickly.
2. Evacuate quickly: Run to the sides perpendicular to the direction of the landslide, the faster the better. Do not run in the direction of the landslide, and do not stay under the landslide.
3. Find a solid shelter: If you can't evacuate in time, quickly look for strong obstacles around you, such as large trees, large rocks, etc., and hide behind them.
4. Hold on to a fixed object such as a tree: If there is no suitable shelter nearby, hold on to a fixed object such as a tree as soon as possible to prevent it from being washed away.
5. Avoid entering dangerous areas, such as rivers, valleys, etc., where landslides may form torrents or dammed lakes, bringing new hazards.
6. Save physical strength: In the process of waiting for rescue, conserve physical strength reasonably, do not shout blindly, and only call for help when you are sure that there are rescuers nearby.
7. Mark well: If you are trapped, place items that indicate your location in a conspicuous location as much as possible, such as brightly colored clothing, so that rescuers can find them.
8. Pay attention to protect your head: Protect your head with items around you, such as school bags and clothes, to avoid being injured by falling rocks.
03
How to prevent landslides
1. Strengthen monitoring and early warning
Establish a professional geological disaster monitoring network, use advanced technical means, such as satellite remote sensing, ground monitoring stations, unmanned aerial vehicles, etc., to monitor the mountain in real time, and timely discover the deformation, displacement and other abnormal conditions of the mountain.
- Improve the disaster early warning system, and timely release early warning information to potentially affected areas through various channels such as text messages, radio, and television, so as to ensure that residents can prepare in advance.
2. Engineering governance measures
Retaining walls, anti-slide piles and other supporting structures are built to increase the stability of the mountain.
Slope cutting and load reduction are carried out on dangerous mountains, and the slope and height of the slope are reduced to reduce the sliding force.
Carry out slope protection, such as laying slope protection nets, planting vegetation, etc., to prevent rainwater erosion and weathering erosion.
3. Drainage measures
Drainage systems such as interception ditches and drainage ditches should be built to divert rainwater away from the mountain in time and reduce the infiltration of rainwater into the mountain.
Carry out groundwater drainage and discharge, lower the groundwater level, and reduce the buoyancy and softening effect of groundwater on the mountain.
4. Rational planning of land use
Avoid large-scale construction activities such as the construction of homes, factories, etc., in areas prone to landslides.
For projects that must be constructed, strict geological survey and engineering design should be carried out, and effective protective measures should be taken.
5. Strengthen vegetation protection
Indiscriminate logging is prohibited, and the vegetation cover of the mountain is protected, and the root system of the vegetation can strengthen the soil and increase the stability of the mountain.
Carry out afforestation and ecological restoration to improve the ecological function and disaster resistance of the mountain.
6. Publicity and education
Carry out publicity and popularization activities on the knowledge of geological disaster prevention and control, and improve residents' awareness of disaster prevention and self-rescue ability.
Organize emergency drills to familiarize residents with escape routes and evacuation methods in the event of a landslide.
7. Establish an emergency plan
Formulate a detailed landslide emergency plan, clarify the responsibilities and tasks of each department, and ensure that rescue and rescue work can be carried out quickly and effectively in the event of a disaster.
8. Regular inspection and maintenance
Carry out regular inspection and maintenance of the prevention and control engineering measures that have been taken to ensure their normal operation and functioning.
Source: Zigui Popular Science