Landslide

The downward and outward movement of slope forming material along surface of separation by falling , sliding and flowing at faster rate is called landslide. The influence of gravity is a constant operation for landslide. Although, landslides are primarily associated with mountainous regions, they can also occur in areas of low relief, especially in surface excavations for highways, buildings, and open pit mines. The geological history and human activities often cause unstable conditions that lead to slope failure.

Usually they occur on steep slopes , where hard and heavy rocks overlie softer. Landslide is one of the most effective and widespread mechanism by which landslide is developed.

The main causes of landslide are not same as the causes of the triggering of the slides. The main triggering factors are:

a. cloud burst (200-1000 mm per day)

b. uncontrolled flow of water on slope surfaces from over flooded steep

c. toe cutting may activate failure by overtopping of rock blocks or slides in colluvium.

d. earthquake vibration

e. blasting vibration

f. flash flood due to glacier lake outburst/ or due to failure of landslide dams, etc.