irrigation distribution works
DESCRIPTION
Powerpoint Presentation on Irrigation Distribution Works by Sri. P.V.Srinivasa Rao, HOD(Civil), MRAGR Govt., Polytechnic College, VizianagaramTRANSCRIPT
LIVE TELECAST ON IRRIGATION ENGINEERING
FOR DCE III YEAR STUDENTS
BY
P.V.SRINIVASA RAO
HEAD OF CIVIL ENGG
MRAGR GOVT POLYTECHNIC
VIZIANAGARAM
DISTRIBUTION WORKS
Major Heads Canals- Types –cross
sections- Alignments Regulators- Drops – Escapes -
Sluices Silt theories - canal Designs Cross drainage works
DISTRIBUTION WORKSPART - II
CANAL REGULATION
Canal Regulation Works
• A Structure constructed to regulate the discharge, velocity and Full supply levels in a canal is known as
“Canal regulation Work”
Types of Canal Regulation Structures
• Canal Head Regulator or Head Sluice• Cross regulator• Distributory Head regulator• Canal Drops or Falls• Canal Out lets or Sluices or Modules• Canal Escapes
Canal Head Regulator It is a structure constructed
at the head of off taking canal Functions• It regulates the flow of water in to main canal• It controls entry of silt in to the canal• It prevents entry of river floods in to the canal
Over View
Features of Canal Head Regulator
• It is placed on U/S of barrage in front of under sluices and aligned at 90o-1100 to the axis of barrage for smooth entry of water
• It contains a raised crest with abutments on both sides
• It is provided with number of vents, separated by piers depending upon the discharge to be carried through it .
Features of Canal Head Regulator
(contd)
• The crest of the HR is kept sufficiently above that of under sluices for controlling the entry of silt in to canal
• Solid apron and cut offs are provided on both U/S and D/S, so as to protect the structure from seepage and hydraulic failures
View
Cross Regulator
It is a structure constructed
across the parent canal at the down
stream of off taking branch canal
View
Cross Regulator
Functions
• To effectively control the entire canal Irrigation system.
• It regulates the flow of water in parent canal
• It facilitates repairs to the canal
contd . . .
Cross Regulator
Functions It controls entry of silt in to canal
It prevents breaches of canals by absorbing fluctuation of discharge
It feeds the off taking canal to meet the full supply demand even at low water levels by heading up View
Distributory Head Regulator
It is a structure constructed across an off taking Distributory
Canal
Functions• It regulates the flow of water in to a Distributory• It controls entry of silt in to canal• It can be used as a measuring Device View
A DISTRIBUTORY HEAD REGULATOR
CANAL REGULATOR
Movie Clippings on Live Structures
BARRAGE AND HEAD REGULATOR
Head Regulator
Off taking Main Canal
at Head Works
Branch Canal
CANAL DROP• A Drop is a vertical step in the bed level
of a canal• Situation: When the slope of natural
ground is steeper than the bed slope of canal, the difference is adjusted by constructing vertical walls at
regular intervals
LOCATION OF CANAL DROPS
NATURAL GROUND LEVEL
CANAL FSL
LONGITUDINAL SLOPE OF CANAL
DROP STRUCTURES
CANAL DROP COMPONENT PARTS1 Body Wall2 U/S & D/S protection works3 Notches and Notch pier4 Bank connections
CANAL DROP - COMPONENTS
TYPES OF CANAL DROPS
• Depending upon the Depth of fall and energy dissipation on D/S, the following types of Canal Drops are in use
TYPES OF FALLS
• 1 Vertical Drop Fall• 2 stepped Fall • 3 Rapid Fall• 4 Montague Fall• 5 Ogee Fall• 6 Notch type fall
VERTICAL DROP FALL
• It consists of a body wall with its crest at the U/S bed Level.
• A water cushion is provided at the foot of body wall on D/S for effective Energy Dissipation
View
STEPPED FALL
FEATURES A stepped Fall will be provided when the
Natural Ground is steeply falling. Stepped body wall will be provided A water cushion and solid apron will be provided on D/S to protect the D/S floor
from scour and uplift
View
RAPID FALL
FEATURES The Down stream profile is provided
in the form of gently sloping glacisThe slope of the glacis will be 1:15
to 1:20 The sloping surface will be formed
with rough stone boulders View
MONTAGUE TYPE FALL
FEATURES It is a modified form of straight glacis fall,
in which a parabolic glacis is provided which is called ‘Montague profile’
The Energy dissipation is more effective View
OGEE FALL
FEATURES The crest and down stream
profile of the body wall will be provided in the form of Convex and Concave curves for smooth gliding of water and also to avoid suction on body wall.
U/S & D/S Protection works will be provided as usual VIEW
NOTCH TYPE FALLS
FEATURES A Notch Pier will be constructed on the top of
body wall in which Notches will be provided Notches may be Triangular, Trapezoidal or
stepped Sill of the Notch will be at Bed Level of canal
on U/S and its top will be at FSL of canal View
Canal Escapes
• It is a structure constructed in a canal bank with a side channel to relieve the excess discharge of the main canal
• The escapes may be provided on the canal at suitable points and also at its tail end
• -contd
Canal Escapes
TYPES OF ESCAPES
1 Surplus Escape ( Regulator Type)
2 Tail Escape (Weir Type)
- contd
Canal Escapes
• Surplus Escape ( Regulator Type) Features: 1 It resembles like a canal regulator with its sill kept at the Bed Level of the canal
2 It can discharge the excess flow of the canal or even empty the entire canal flow through its gate controlled vents View
Canal Escapes ( Weir Type )
Features In this type of Escape, the crest of the weir is kept at the FSL of the canal to drain off the excess discharge of the canal in to a natural drain Protective works will be provided on D/S to prevent scouring
View
IMAGES OF TANK ESCAPES
( Weir Type )
VIEW
CANAL OUTLETS
• It is a structure built at the head of water course to regulate water flow to the fields
• It is also called ‘Sluice’ or ‘Module’
( contd )
CANAL OUTLETS
FEATURESIt receives water from a Minor or
a Distributory and supplies to the fields
It facilitates equitable distribution of available water to the users
contd
CANAL OUTLETS
Types of outlets or Modules
1 Non Modular outlets :- Discharge through the outlet depends upon the difference of head between the distributory and the water course Examples: Pipe outlets and Masonry Sluices - - contd
CANAL OUTLETS
PIPE OUTLET-FEATURES A pipe is placed in the bank of a Distributory to draw the water for supplying to the water course Masonry Head walls are to be constructed at both the ends of
the pipe View
CANAL OUTLETS
2 Modular outlets :- Discharge
through the outlet is constant and is independent of the difference of head between the distributory and the water course
Examples: Gibb’s Module
GIBB’S MODULE
FEATURESIt consists of a pipe with a bell mouth
entrance.The discharge end of the pipe is in
the form of a raising spiral pipe in which free circular flow is developed.
The discharge is constant VIEW
REVIEW
Types of Canal Regulation Structures
• Canal Head Regulator or Head Sluice• Cross regulator• Distributory Head regulator• Canal Drops or Falls• Canal Out lets or Sluices or Modules• Canal Escapes
TYPES OF FALLS
• 1 Vertical Drop Fall• 2 stepped Fall • 3 Rapid Fall• 4 Montague Fall• 5 Ogee Fall• 6 Notch type fall
Canal Escapes
TYPES OF ESCAPES
1 Surplus Escape ( Regulator Type)
2 Tail Escape (Weir Type)
- contd
CANAL OUTLETS
• It is a structure built at the head of water course to regulate water flow to the fields
• It is also called ‘Sluice’ or ‘Module’
( contd )
THE END
TREPEZOIDAL NOTCH FALL
NEXT
VERTICAL DROP FALL
BACK
NOTCH TYPE FALL
NEXT
RAPID FALL
BACK
OGEE FALL
BACK
STEPPED FALL
Water Cushion
Back
MONTAGUE FALL
U/S FSLD/S FSL
BACK
SURPLUS ESCAPE(REGULATOR TYPE)
NEXT
BACK
SURPLUS ESCAPE(Regulator type)
SURPLUS ESCAPE(WEIR TYPE)
NEXT
SURPLUS ESCAPE(WEIR TYPE)
NEXT
SURPLUS ESCAPE(WEIR TYPE)
BACK
PIPE OUTLET
IMAGES
GIBB’S MODULE
BACK
A water course taken off from a Minor Distributory
NEXT
A WATER COURSE WITHPIPE OUTLET
NEXT
A view of water course
NEXT
Regulation of water to the fields from water course
BACK
FUNCTIONING OF HEAD REGULATOR
IMAGE
Barrage
River
Head Regulator
Off taking Canal
Features
AN OVER VIEW OF RIVER HEAD AN OVER VIEW OF RIVER HEAD WORKSWORKS
Cross & Distributory regulators
BACK
JUNCTION OF MAIN AND BRANCH CANALS
U/S
D/S CROSS REGULATOR
Distributory Head Regulator
D/S
Home
JUNCTION OF MAIN AND BRANCH CANALS
U/S
D/S CROSS REGULATOR
Distributory Head Regulator
D/S
Home
D/S view of Head Regulator
BACK
Trapezoidal Drop
BACK