GTU last year question papers
GUJARAT TECHNOLOGICAL UNIVERSITY
BE SEM-VII Examination-Nov/Dec.-2011
Subject code: 170602
Subject Name: Irrigation Engineering
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) Explain the procedure of designing an irrigation channel
with Kennedy’s theory, when Q, N, m and S are given.
(b) Explain the terms (i) Duty (ii) Delta and (iii) Base period.
Derive the relation between Duty, Delta and Base period.
Q.2 (a) Describe the method of design of a lined canal.
(b) Explain Khosla;s method of independent variables.
(b) Write the design features for Boarder Strip Flooding
Q.3 (a) Describe the following irrigation methods with sketches
(i) Check basin flooding method.
(ii) Drip irrigation method
(b) (i)Find the time required to cover an area of 0.1 hectares
when a tube well is discharging at the rate of 0. cumec
for irrigating rabi crop. Average depth of flow is expected
to be 7.5 cm. Average infiltration rate for the soil may be
taken as 5 cm/hour.
(ii) Furrow 100m long and 1m apart having longitudinal
slope of 0.3 percent are initially irrigated by a non-erosive
stream for 80 minutes. The stream size is then reduced to
40% and continued for another 35 minutes. Determine the
average depth of irrigation.
Q.3 (a) Describe the method of designing an irrigation canal based
on Lacey’s theory.
(b) Using Kennedy’s theory, design a channel section for the
Discharge, Q=25 cumec, Kutter’s N=0.0225,
Critical velocity ratio, m=1, Side slope =1/2:1 and
Bed slope, S=1/5000
Q.4 (a) (i) Explain the term ”Diversion Head Work” and clearly
mention its different functions.
(ii) Explain Bligh’s Creep Theory in details.
(b) A canal takes off from a reservoir to irrigate the areas as
shown in the Table below. 40% of the water required for
irrigation is assumed to be available directly from
precipitation. Channel conveyance losses are 15%.
Reservoir losses are 10%. What would be the capacity of
the reservoir needed? (The reservoir to be filled only once a
Crop Base period
Duty at field
Wheat 120 1800 500
Sugarcane 320 800 600
Rice 120 900 300
Cotton 200 1400 1200
Bajra 100 1200 50 0
Q.4 (a) State and explain the cause of failure of Structure founded on permeable soil.
(b) A weir has a solid horizontal floor length of 50 m with two
lines of cutoff 8 m depth, below the riverbed at its two
ends. The floor thickness is 1 m at the upstream end and 2
m at the downstream end, with its upper level being in
flush with the river bed. For an effective head of 5 m over
the weir, calculate the uplift pressure at the two inside
corner points (junction of bottom of floor with the cutoff)
and also exit gradient.
Q.5 (a) Describe with the help of sketches various types of Crossdrainage
(b) (i) What do you understand by a fall in canal? Why it is
(ii) What are the causes of water logging?
Q.5 (a) What is weir? How does it differ from a barrage structure?
Give relative advantages and disadvantages with their
(b) (i) What are the functions of a canal head regulator?
(ii) Explain the terms with a sketches wherever applicable
(1) Sheet piles (2) D/S protection (3) U/S protection.