Gujarat University 2007 B.E Civil Engineering Irrigation - Question Paper
V203 A Candidate's Seal No . ____
GUJARAT UNIVERSITY B.E. Sem. VII (Civil) Examination Irrigation
Thursday 27th December, 2007] |Tinae : 3 Hours
Max. Marks : 100
Instructions : (I) Attempt ail questions.
(2) Answer to the two sections must be written in separate answer books.
(3) Assume suitable data if require;
(4) Figures to the right indicate full marks.
I
SECTION - I
1 ( a ) Expalin the following terms: 16
(i ) C.C.A. (ii) Intensity of irrigation (iii) Kor depth (iv ) Outlet factor ( v ) Overlap allowance ( vi) Water use efficiency.
( b ) Explain the term "Sustainable development. Why environment monitoring & assessment of irrigation projects is needed?
( c ) Explain direct irrigation scheme with a neat sketch.
OR
1 ( a ) Discuss briefly the benefits as well as the ill effects of irrigation. 16 ( b ) Explain the term duty & delta. Derive a relationship between the two for a given base period.
( c ) Determine the storage capacity of soil from die following data.
Field capacity ~ 35%; Wilting point =12% Root zone depth = i. 1 m; Dry unit weight of Soil = 1750 kg/m'. Also determine the depth of water required in the field if irrigation water is applied when moisture content falls to 20% & (he field application efficiency is 80%. Considering conveyance loss as 12%'of outlet discharge; Calculate the depth of water needed at canal outlet.
2 ( a ) Explain the working of a sprinkler with a neat sketch. 16
( b ) What is the necessity of Crop rotation? How fertility of soil can be maintained?
f
( c ) A tube well is having discharge of 500m Vhr. It has to irrigate 150 hectares of wheat & 70 hectares & sugarcane during a year. The delta for wheat & sugercane are 0.6m & 1.8m respectively. How many hours a tubewell should run to irrigate Wheat & sugercane?
OR
2 ( a ) Discuss the drawbacks of Kennedys theory for design of canal 111 aUuviom Soil. 16 ( b ) Describe briefly the various considerations made in the alignment of an irrigation canal.
( c ) Design a trapezoidal concrete lined canal, it cany a discharge of400m3/s. at a slope of 1 in 5000. lake side slope of canal 1.5 : 1 & Manning's Rugosity coefficient as 0.012. Assume B/D ratio to be 5.
j
3 ( a ) Write short notes on any three : H
( i ) Seepage failure of earth dam (ii ) Classification of irrigation canal
(iii) Waterlogging & its control ( iv ) Assessment of irriagation water.
4 ( a ) Draw a neat sketch of diversion headworks & explain functions of each component.
( b ) Discuss various modes of failure of Gravity Dam.
( c ) Differentate between (i) Weir & Barrage (ii) Silt excluder & silt ejector.
OR
4 ( a ) What are the tactor which aftect the selection of site for dam? Discuss them in brief.
( b ) Under which sotuation the Bandhara irrigation is adopted & what are the main points to be considered for its site selection?
( c ) Following data refers to homogeneous earth dani; Top widtli = 4m. Head of water u/s = 16m u/s & d/s slope = 2.5 H : I V & 2H : IV respectively. Free board = 2.5m. Harizontal filter 37m from d/s toe. Coefiicient of permeability K = 0.008 cm/sec. Calculate seepage per meter length of dam.
5 ( a ) Discuss various methods used for energy dissipation below spillway.
( b ) What do you mean by the elementry profile of a grawity dam? Discuss in brief the forces acting on the dam, while determining elementary profile.
( c ) Explain step by step procedure to draw phreatic line for earth dam.
OR
5 ( a ) What do you understand by a fail in a canal? Why is it necessary? How do you select its
location?
( b ) Define the term exit gradient. What is the importance of exit gradient? How would you check the exit gradient?
( c ) A concrete gravity dam lias maximum waterievel 305.0 m, bed level 225.0m, top R.L of dam 309.0 m, d/s face slope starts at R.L 3000 m d/s slope slope 2 : 3, tail water is nil. u/s face of dam is vertical, centreline of drainage gallery is 8m d/s of u/s face, uplift press is 100% at heel, 50% at line of gallery & zero at toe. Weight of concrete is 2.4 t/m\ Considering only weight, water pressure & uplift determine (i) Maximum vertical stresses at the toe & heel of dam
(ii) Major principal stresses at toe of dam and (iii) intensity of shear stress on a horizontal plane.
6 ( a ) Write short notes on any three :
( i ) Head regulator ( ii) Filter criteria for earth dam ( iii) Spillway gates ( iv ) Canal lining & its advantage.
|
Attachment: |
| Earning: Approval pending. |
