Barriers are provided in order to ensure the protection of people, livestock, structures from unstable rock fragments, debris, snow slide (in case of avalanche) on slope surfaces and areas surrounding them, which are lying in the vicinity of the installed barrier locations; thereby facilitating the smooth functioning of livelihood without any hindrance.
Types of Barriers
- Rockfall Barrier
- Debris flow Barrier
- Avalanche Barrier
Significance and Suitability – Rock Fall Barrier
It is designed to provide protection around slope areas from falling rocks, boulders, shooting stones. It consists of mesh, cable anchors, posts, energy dissipater system. The Rockfall Barrier’s function is to reduce the energy of falling rock and trap it into the barrier.
Types: Hinged Rockfall Barrier, Fixed Rockfall Barrier
- Hinged Rockfall Barrier– As the name suggests, it is flexible in nature. In the barrier, a mesh is draped around the posts, which are held by pins, which act as hinges onto the ground. They are constructed with minimal foundation and allows for easy installation. They can be constructed on any difficult terrain with ease. They have energy absorbers installed on them, allowing them to take the impact of rock falling with high kinetic energy and transfer it from mesh to post and then to pins and partly to ground. These types of barriers have energy ranging up to 5000 kJ with approved heights of 6 to 7 meters.
- Fixed Rockfall Barrier– They are rigid in nature due to their foundation. These foundations require more space, and it does not contain energy absorbers, ropes. The energy from a falling rock is carried by a combined system of mesh and foundation. This system requires posts heavier than the hinged rockfall barrier. Proper space near installed fixed barrier facilitates easy cleaning of the rock debris.
Debris Flow Barrier
The debris flow is prominent during liquefied landslides, flash floods. This barrier traps the debris and allows the flow of only mud, water. They are installed perpendicular to flow direction. They help to reduce the velocity and erosion potential. Depending on the intensities, they are designed based on its flow, gully net for narrow, and for wide and broad flow mesh, post system is used.
They are used for Avalanche protection. During Avalanche, snow slide occurs rapidly down the slope, destroying and blocking everything which comes in its way. Two types of Avalanche barriers are used:
(a)Static Avalanche Barrier restrains the avalanche initiation by packing the snow at the initiation itself.
(b)Dynamic Avalanche Barrier collects the running snowslide, which has already been initiated.