What causes landslides?

The formation of landslides is divided into rock and soil types, geological structural conditions, and topography.

There are four kinds of conditions, hydrogeological conditions.

Causes of landslides:

1) Geotechnical type. Rock and soil are the material basis for landslides.

2) Geological and tectonic conditions. The condition that the rock and soil that make up the slope can only slide downward when it is cut and separated into a discontinuous state by various structural planes. At the same time, the tectonic plane provides a channel for water currents such as rainfall to enter the slope. Kill the fierce.

3) Topographic and geomorphological conditions. Landslides can only occur if they are in a certain landform location and have a certain slope.

4) Hydrogeological conditions. Groundwater plays a major role in the formation of landslides.

The causes of landslides are: excavation of the foot of the slope, drainage system, and blasting.

1. Excavated at the foot of the slope.

The construction of railways, highways, houses and factories on the mountain often slides due to the loss of support in the lower part of the slope. For example, some railways and highways in the southwest and northwest of China have been vigorously blasted and forcibly excavated during construction, and landslides have occurred on the slopes one after another, bringing harm to road construction and operation.

2. Drainage system.

The overflow and leakage of canals and pools, the discharge of water and wastewater for industrial production, and agricultural irrigation are all easy to make the water flow infiltrate into the slope, increase the water pressure of the pore failure, soften the rock and soil, and increase the bulk density of the slope, thereby promoting or inducing the occurrence of landslides. The water level of the reservoir fluctuates sharply, which increases the hydrodynamic pressure of the slope, and can also cause landslides to occur on the slope and bank slope.

3. Caused by blasting.

The blasting effect of splitting the mountain and mining can cause the rock and soil of the slope to be broken by vibration and produce landslides; Indiscriminate felling on the slope and depriving the slope of protection will facilitate the infiltration of water bodies such as rainwater and induce landslides. The combination of human action and adverse natural action makes it easier to promote the development of landslides.

Landslide prevention and real-time monitoring countermeasures:

1. Build a geological disaster monitoring and forecasting system: establish a monitoring team that combines professional personnel with group measurement and group prevention, establish a monitoring network based on a professional team for important geological disaster points, and establish a monitoring network based on group measurement and group prevention for other geological disaster points, and combine it with the guidance of a professional team and regular inspections.

2. Establish a geological disaster analysis system in mountainous areas: after a landslide body is in danger, the local geological disaster sock combustion prevention and control work headquarters will convene a meeting of local disasters and related experts to analyze the information collected by the monitoring and early warning system, judge the state and early warning level of the landslide body, estimate the impact range of the surge, and form consultation opinions for local decision-making reference.

1. To understand how landslides occur, we first need to know how mountains are structured. A mountain is not entirely made of sand, its surface is soil, mixed with impurities such as gravel, rotten wood, and rotting animal carcasses, and the soil is under pressure to form a relatively solid layer of rock.

2. The soil is piled on the rocks like a pile of building blocks, and this pyramid-like structure is actually not stable. On the slopes, gravity makes the soil want to roll to the bottom of the mountain, but usually the friction of the rocks below pulls the soil and leaves it halfway up the mountain. You can imagine a poster that is taped to the wall with scotch tape, and if the scotch tape gradually fails, the poster will fall off, and the landslide is also the mud and sand on the surface of the hillside.

3. Rain will not only wash away dust, but also moisturize the soil. If you've ever built a fort building with sand, you know that if the sand is too dry, it's hard to build, and adding a little water can increase the stickiness of the sand, making it easier to build a stable building. But if there is too much water, the whole building will fall apart.

4. The slopes of the mountains will be eroded by wind and rain for a long time, as well as various other natural forces, and slowly become fragile, like a crumbling poster.

5. After a rainfall, the rain penetrates into the soil, it will not only reduce the friction between the soil and the rocks below, but also the rain-soaked soil will become heavier, and this rain will become the last straw that crushes the camel. Large chunks of weak soil slide down the hillside, burying houses and roads below the hillside, and even blocking the river. If the rainfall is particularly heavy, there is a risk of mudslides, in which the soil does not fall off in chunks, but becomes a torrent of mud.

6. Tree vegetation plays a huge role in protecting the soil, plants will take root in the soil in order to absorb water and nutrients, while some tall trees have thicker and more intricate roots, these roots can extend deep into the ground, down to the hard rock, the roots of these plants are like glue that firmly holds the soil and rock together.

7. People will damage the ecology and affect the land structure due to excessive cutting down of trees, opening up mines, building roads and other activities. Without tree vegetation, the soil on the hillside becomes looser and more prone to disintegration as if it had lost its glue, causing landslides. In addition to rainfall, shaking caused by ** can also trigger landslides.

8. Therefore, those bare mountains lose not only their green coat, but also their protective barrier against landslides.