1 Soil, climate, vegetation and other conditions are certain, that is, the landslide relationship is not directly related to these factors, but only related to the slope and is not affected by the earthquake.

The hillside model is continuous, that is, a continuous surface.

Mountain objects are regarded as particles, regardless of their volume and surface shape, only their mass is considered.

Modeling:

Condition of balance by object: f+F=Gsin

The viscosity of an object is F=a*k*dv\dx, where a is the contact area, k is the viscosity coefficient, v is the relative velocity, and x is the average distance between objects.

T is the time when the object accelerates to V, and H is the distance that the object slides during this time.

mgsin =？ mg cos + a*k*dv\dx

dv=mg(？ cos - sin )dx\a*k

v= mg(？ cos - sin )*x\a*k

By kinetic energy theorem: 0.5mv? =mgh-(？ mgcos + a*k*v\x)vt

V= mg(？ Cos-sin )*x\a*k is substituted into the above formula: solution.

Get:

=0.5arccos[4mgxha？ k？ -2aktm？ g？ x？ -m？ g？ x？ (MX+2 Akt)]-0.5φ

Where: tgφ = [2? (mx+2akt)+2？ akt]\[2mx+6akt-(mx+2akt)]

Analysis:

But in fact:

T→0 and h→0, so: =0.5arccos(m? g？ x？ )-0.5Φ

At this time: TG φ = 2? \(2- 1)

In the above formula, x is an important factor affecting the landslide angle. When x increases, it decreases, that is, the critical angle of landslide decreases, which is a dangerous increase. X represents the average distance between objects. The bigger the gap between earth and rock, the easier it is for the mountain to slide. The size of the gap is directly related to many other factors, which we will discuss next.

1. Weather: When it rains, the humidity of the land will increase, the viscosity of the soil will decrease, and the critical slope will decrease. Under the impact of heavy rain, the soil on the hillside will be unstable, slide down the slope and mix with the water body, and scour and cut to form a slope debris flow hanging on the steep slope.

2. Soil quality: the soil quality is soft, the gap between particles is large, and the critical slope is reduced.

3. Vegetation: Vegetation is conducive to increasing the adhesion of land, improving the viscosity of land and preventing landslides.

4. Human influence: human activities such as destroying vegetation and digging and blasting mountains will induce landslides.

Examples and early warning mechanism: send people to measure local soil quality regularly, measure data, and issue reports in weather forecast, especially in the case of rain and earthquake. When the danger was discovered, the government organized local residents to evacuate in time.