Creep is the imperceptibly slow, steady, downward movement of slope-forming soil or rock. Movement is caused by shear stress sufficient to produce permanent deformation , but too small to produce shear failure. ... Progressive, where slopes are reaching the point of failure as other types of mass movements.
What is creep mass movement?
Creep is the imperceptibly slow, downslope movement of soil and earth materials . Rates of movement are often only a few centimeters per year, but the inevitability of creep can severely impact shallowly-placed structures.
How does creep occur mass movement?
Creep, in geology, slow downslope movement of particles that occurs on every slope covered with loose, weathered material . Even soil covered with close-knit sod creeps downslope, as indicated by slow but persistent tilting of trees, poles, gravestones, and other objects set into the ground on hillsides.
What causes creep to occur?
In materials science, creep (sometimes called cold flow) is the tendency of a solid material to move slowly or deform permanently under the influence of persistent mechanical stresses. It can occur as a result of long-term exposure to high levels of stress that are still below the yield strength of the material .
How does soil creep occur?
Soil creep usually occurs during and after rain . The amount of creep caused by one rainfall has a positive correlation with the amount of rain and increase in soil moisture. ... Soil gradually concentrates directly below the knick point, and the slope becomes steeper and unstable.
What is the slowest type of mass movement?
The slowest and least noticeable, but most widespread of the slow mass wasting categories is creep . Creep involves the entire hillside, and is characterized by very slow movement of soil or rock material over a period of several years.
What are four ways to prevent mass movements?
Mass movement control must be primarily preventive: e.g., mapping vulnerable zones, drawing up a land use plan, banning building work or any modification of slopes, and protection in the form of coppice forests.
What are the 5 types of mass movement?
- Rockfall. Bits of rock fall off the cliff face, usually due to freeze-thaw weathering.
- Mudflow. Saturated soil (soil filled with water) flows down a slope.
- Landslide. Large blocks of rock slide downhill.
- Rotational slip. Saturated soil slumps down a curved surface.
Which mass movement is the fastest?
Landslides and avalanches can move as fast as 200 to 300 km/hour. Figure 3. (a) Landslides are called rock slides by geologists. (b) A snow avalanche moves quickly down slope, burying everything in its path.
What type of mass movement is flow?
d) Flows: A flow is a spatially continuous movement in which shear surfaces are short lived, closely spaced and usually not preserved after the event. The distribution of velocities in the displacing mass resembles that in a viscous fluid.
What are the 3 stages of creep?
Primary Creep: starts at a rapid rate and slows with time. Secondary Creep : has a relatively uniform rate. Tertiary Creep: has an accelerated creep rate and terminates when the material breaks or ruptures. It is associated with both necking and formation of grain boundary voids.
How do you stop creep failure?
In general, there are three general ways to prevent creep in metal. One way is to use higher melting point metals , the second way is to use materials with greater grain size and the third way is to use alloying. Body-centered cubic (BCC) metals are less creep resistant in high temperatures.
What is creep and fatigue?
Creep And Fatigue are the phenomenon that lead to deformation and eventually failure of Components . Fatigue is a situation in which component is subjected to cyclic loading. Creep is a situation in which a component experiences deformation under constant load with time as it is put into use.
What are signs of soil creep?
Progressive, where slopes are reaching the point of failure as other types of mass movements. Creep is indicated by curved tree trunks, bent fences or retaining walls, tilted poles or fences, and small soil ripples or ridges .
How can we reduce soil creep?
- Plant Grass and Shrubs. Grass and shrubs are very effective at stopping soil erosion. ...
- Use Erosion Control Blankets to Add Vegetation to Slopes. ...
- Build Terraces. ...
- Create Diversions to Help Drainage.
What is an example of a soil creep?
One example of soil creep in real life is from the wealthy Caribbean nation of Trinidad and Tabogo . ... The movement of the soil caused instability and triggered other, more dramatic forms of mass wasting such as debris flows, and the road required reconstruction to combat the one-inch-per-year creep in the area.
