Irrigation Engineering and Hydraulic Structures

Preface
Contents
1
Introduction
1.1 PRACTICE OF IRRIGATION IN INDIA
1.2 SCOPE
1.3 STATUS OF IRRIGATION IN INDIA
1.4 IMPACT OF IRRIGATION ON HUMAN ENVIRONMENT
1.5 IRRIGATION SYSTEMS
1.6 COMMAND AREA DEVELOPMENT
1.7 DEVELOPMENT OF AN IRRIGATION PROJECT
2 Water Requirement of Crops
2.1 CROPS AND CROP SEASONS
2.2 DEFINITIONS OF TERMS USED IN CALCULATION OF IRRIGATION DEMAND
2.3 QUALITY OF IRRIGATION WATER
2.4 SOIL WATER RELATIONSHIP
2.5 SOIL CHARACTERISTICS FROM IRRIGATION CONSIDERATIONS
2.6 CONSUMPTIVE USE
2.7 FIELD IRRIGATION REQUIREMENT (FIR)
2.8 FREQUENCY OF IRRIGATION
2.9 IRRIGATION METHODS
EXERCISES
3
Hydrology
3.1 SCOPE OF HYDROLOGY
3.2 RAINFALL
3.2.1 Types of Rainfall
3.2.2 Measurement of Rainfall
3.3 SURFACE RUN–OFF
3.3.1 Strange Curves
3.3.2 Stanford – Watershed Model
3.3.3 Rational Approach
3.4 FLOOD FLOW CALCULATION
3.4.1 Empirical Formulae for Flood Calculation
3.4.2 Unit Hydrograph Method
3.5 IUH, S AND SYNTHETIC UNIT HYDROGRAPH
3.6 TO GET UNIT HYDROGRAPH OF DIFFERENT DURATION FROM THAT OF GIVEN DURATION
3.7 RAINFALL/FLOOD FREQUENCY ANALYSIS
EXERCISES
4
Ground Water
4.1 GROUND WATER OCCURRENCE AND RESOURCES
4.2 WELL IRRIGATION
4.3 WELL HYDRAULICS
4.3.1 Steady State Discharge from Unconfined Aquifer
4.3.2 Steady State Discharge from Confined Aquifer
4.4 RECUPERATION TEST
4.4.1 Safe Yield Under a Constant Depression Head
4.4.2 Interference of Wells
4.5 WELL SHROUDING
4.6 WELL DEVELOPMENT
4.7 COLLECTOR OR RADIAL WELL
4.8 WELL LOSSES
4.9 UNSTEADY GROUNDWATER FLOW TOWARDS WELLS
EXERCISES
5
Reservoir Planning
5.1 INTRODUCTION
5.2 TYPES OF RESERVOIRS
5.3 INVESTIGATION FOR RESERVOIR SITES
5.4 ZONES OF STORAGE IN A RESERVOIR
5.5 SEDIMENTATION IN RESERVOIR
5.6 USEFUL LIFE OF RESERVOIR
5.7 FACTORS AFFECTING SELECTION OF RESERVOIR SITE
5.8 DETERMINATION OF RESERVOIR CAPACITY FROM MASS CURVES
5.9 RESERVOIR LOSSES
5.10 RESERVOIR FLOOD ROUTING
5.11 FIXING HEIGHT OF DAM FROM RESERVOIR WORKING TABLE
EXERCISES
6
Design of Gravity Dams
6.1 INTRODUCTION
6.2 FORCES ACTING ON GRAVITY DAMS
6.3 THEORETICAL PROFILE OF GRAVITY DAM
6.4 HIGH AND LOW GRAVITY DAM
6.5 FACTOR OF SAFETY FOR DESIGN OF GRAVITY DAM
6.6 PRACTICAL PROFILE OF GRAVITY DAM
6.7 DRAINAGE GALLERY
6.8 JOINTS IN GRAVITY DAM
6.9 FOUNDATION TREATMENT
6.10 TYPES AND FUNCTION OF GALLERIES
EXERCISES
7
Spillways and Gates
7.1 GENERAL
7.2 OGEE SPILLWAY
7.3 DESIGN OF STILLING BASINS
7.4 DESIGN OF SKI-JUMP BUCKET AND ROLLER BUCKETS
7.5 SIPHON SPILLWAYS
7.5.1 Saddle Siphon
7.5.2. Volute Siphon
7.5.3 Chute Spillway
7.5.4 Side Channel Spillways
7.5.5 Shaft Spillway
7.6 LIMITING HEAD OF SIPHON SPILLWAY
7.7 SPILLWAY CREST GATES
7.8 DESIGN OF AIR VENT FOR VERTICAL LIFT GATES PROVIDED IN SUPPLY SLUICES OF THE DAM
7.9 CAVITATION AND VIBRATION PROBLEM IN HYDRAULIC STRUCTURES
EXERCISES
8 Arch and Buttress Dams
8.1 INTRODUCTION
8.2 TYPES OF ARCH DAMS
8.3 DESIGN OF ARCH DAM BY THIN CYLINDER THEORY
8.3.1 Limitations of Thin Cylinder Theory
8.3.2. Elastic Arch Theory
8.3.3 Trial Load Analysis
8.4 OTHER VARIETIES OF ARCH DAM
8.4.1 Constant Angle Arch Dam
8.4.2 Variable Radius (or Angle) Arch Dam
8.4.3 Doubly Curved Type Arch Dam
8.5 BUTTRESS DAMS
EXERCISES
9
Earth Dams
9.1 EARTH DAM AND ITS COMPONENT PARTS
9.2 ESTIMATION OF SEEPAGE THROUGH HOMOGENEOUS EARTH DAM
9.2.1 Homogeneous Earth Dam Section with Horizontal Filter at Toe
9.2.2 Homogeneous Earth Dam Section without Horizontal Filter at Toe
9.2.3 Phreatic Line for Zoned Earth Dam
9.3 DESIGN CONSIDERATIONS
9.3.1 Case of d/s Slope for Steady State Seepage
9.3.2 Stability of Foundation against Horizontal Shear (Fig. 9.7)
9.3.3 Stability of Earth Dam against Horizontal Shear at the Base of the Dam
9.3.4 Stability of d/s Slope against Horizontal Shear at Base (refer Fig. 9.9)
9.3.5 Stability of u/s Slope against Horizontal Shear at Base
9.4 CAUSES OF FAILURE OF EARTH DAM
9.5 FILTERS: CRITERIA AND DESIGN
EXERCISES
10
Canal Head Works
10.1 BARRAGE AND WEIRS
10.2 DIFFERENT UNITS OF CANAL HEAD WORKS
10.3 DESIGN OF WEIR
10.4 BLIGH’S AND KHOSLA’S THEORIES
10.4.1 Bligh’s Creep Theory
10.4.2 Lane’s Weighted Theory
10.4.3 Khosla’s Theory
10.5 KHOSLA’S METHOD OF INDEPENDENT VARIABLES
10.6 SALIENT FEATURES OF DESIGN OF WEIR ON PERVIOUS FOUNDATION
10.7 NUMERICAL PROBLEMS ON WEIR DESIGN:
10.8 SEDIMENT CONTROL AT CANAL-HEAD WORKS
10.9 RIVER TRAINING WORKS FOR CANAL HEAD WORKS
EXERCISES
11
Distribution System
11.1 GENERAL
11.2 CANAL SYSTEM
11.3 ALIGNMENT OF CANALS
11.3.1 Curves on Canal Alignment
11.4 LOSSES AND TYPES OF CROSS-SECTION FOR CANAL
11.5 DESIGN OF ALLUVIAL CHANNELS
11.5.1 Kennedy’s Method
11.5.2 Lindley’s Equation
11.5.3 Lacey’s Regime Theory
11.6 WATERLOGGING
11.6.1 Causes of Waterlogging
11.6.2 Effects of Waterlogging
11.6.3 Remedial Measures to Control Waterlogging
11.6.4 Design of Closed Drain System for Effective Drainage of Waterlogged Areas
11.7 CANAL LINING
11.7.1 Economics of Canal Lining
11.7.2 Types of Lining
11.8 DESIGN OF LINED CANALS
EXERCISES
12
Canal Structures
12.1 DISTRIBUTION AND MEASUREMENT STRUCTURESFOR CANAL FLOWS
12.2 CANAL OUTLETS
12.2.1 Parameters Controlling Behaviour of Outlets
12.2.2 Non-Modular Pipe Outlets
12.2.3 Kennedy’s Gauge Outlet
12.2.4 Modular Outlet
12.3 CROSS-DRAINAGE WORKS (C.D. WORKS)
12.3.1 Aqueducts
12.3.2 Super Passage
EXERCISES
13 Sediment Transport in Alluvial Canals
13.1 TRANSPORT OF SEDIMENT IN ALLUVIAL CANALS
13.2 THRESHOLD MOVEMENT
13.3 SHIELD’S ENTRAINMENT FUNCTION
13.4 BED LOAD FORMULA BY EINSTEIN
13.5 BED LOAD FORMULA BY MEYER–PETER
13.6 DU-BOIS BED LOAD FORMULA
13.7 SUSPENDED LOAD CONCENTRATION
13.8 TRACTIVE FORCE METHOD OF DESIGN OF STABLE CHANNEL
EXERCISES
14 River Training Works and Flood Control
14.1 GENERAL
14.2 CLASSIFICATION OF RIVERS
14.3 RIVER TRAINING WORKS
14.3.1 Marginal Bunds or Levees
14.3.2 Guide Banks or Guide Bunds
14.3.3 Groynes or Spurs
14.3.4 Cut-Off
14.3.5 Pitched Islands
14.3.6 Bundalling
14.4 FLOOD CONTROL
14.4.1 Flood Absorption Capacity of Reservoirs
14.4.2 Flood Forecasting Methods
14.4.3 Channel Improvement
EXERCISES
15 River Flow Measurement
15.1 NEED FOR DISCHARGE MEASUREMENT IN RIVER SECTION
15.2 CURRENT METERS
15.2.1 Vertical Axis Meter
15.2.2 Horizontal Axis Meter
15.3 CROSS-SECTIONAL AREA-VELOCITY METHOD TO MEASURE DISCHARGE
15.4 SLOPE AREA METHOD
15.5 STAGE-DISCHARGE RELATIONSHIP
References
A. STANDARD BOOKS AND TREATISES
B. TECHNICAL PAPERS AND REPORTS
Subject Index