Component parts of a weir ?
- Body wall of the weir
- Upstream solid apron
- Apron on downstream side
- Curtain walls on Upstream & Downstream
- Talus on Upstream & Downstream
- Shutter on the crest of weir
Body wall of the weir
- It is a wall which is constructed to raise the water level on u/s
- To raise water level on u/s
- To resist water pressure
- To resist uplift pressure
Upstream Solid Apron
- Protect weir from erosive forces during floods
- Length of apron depends upon discharge in river and length of weir
- To prevent any leakage in the sub soil
Apron on Downstream Side
- To reduce the kinetic energy of water
- Length depends upon height of fall of water nature of soil discharge in river
- Apron is extended up to the point where there is no scope for erosion
- It Should have sufficient width to resist uplift pressure
Curtain walls on UpStream & DownStream
- Upstream curtain wall
- To reduce uplift pressure
- Length depends on nature of sub soil
- To increase length of the creep
- To reduce exit gradient
- Downstream curtain wall
- Protect downstream flow from uplift pressure.
- To resist kinetic energy of water increase length of creep
Shutters
- Provide on the crest It can be raised during flood To resist water pressure
- Protect downstream flow from uplift pressure.
- To resist kinetic energy of water increase length of creep