Serial
No.
Q

'Elngineenng1_$_etiuc
2

.C-FT_F-=MDJB

CIVIL
.,

ENGINEERING
PaperII

(Conventional)

i

INSTRUCTIO
QuestionNo. I is compulsory.Out of the remaining
SEVEN questions,attemptany FOUR questions.
Each question carries 40 marks.

Thenumberof markscarried by eachsubdivisionof a
questionis indicatedat the end of the subdivision/
question.Wherevera questionis attempted,all its

subdivisionsmustbe attempted
Answersmustbe written"onlyin ENGLISH.
Assumesuitable data, if found necessary,and
indicatethe sameclearly.
Unlessindicatedotherwise, notationsand symbolshave
their usual meanings.

Important note :

All parts and sub-parts of a question "beingattempted

are to be answeredcontiguouslyon the answer-book.
That is, all theparts and sub-partsof onequestionare

tobecompleted
before
attempting
thenext"
question.
Pagesleft blankin the answer-book,
If any,are to be
struck out. Answers that follow blank pages may not
be given credit.

1.

(a) (i)

The velocity in a boundary layer over a
horizontal at

plate held in a free stream

with a velocity -U is given as

-It-34-*a+b11+c112
where u is velocity at y and U at -8 and

11= y/5 ; y and 6 are measureof normal to
_theat
efcients

plate. Determine the value of coa, b and. c using appropriate

boundary-conditions. If the shear stress on
. .
theplate-.15
gtven
To=K1.1U findthevalue
of K.

4

(Contdt)

(ii)

A Pelton wheel has a meanbucket speedof
10 m/sec with a jet of water owing at the

rate of 0-7 m3/secunder a head of 30 m.
The bucket deflect the jet through an angle
of 160°. Calculate power given by water to

the runnerand the hydraulicefficiencyof
theturbine.Assumeefficiencyof thenozzle
as 0-98.

4

(b) What are the different types of cross drainage
works that are required when a canal crosses a

naturaldrainage? Draw a planview.of an aqueduct
showing all details.

8

(c) What is a water bearing stratum ? On what
basis ground water flows in it ? What is the
difference between Specic Yield and Specic
Retention

(d) (i)

?

8

Whatdoyouunderstand
by index properties
of soil ? Explain and list the properties
under different categories.
4

(ii)

What is meant by earth pressure at rest,
active earth pressure and passive earth

pressure"'2,
Explain the differencein terms
of wall

movement.

4

(e) What are the factorsto be considered in selection

of a gauge? Write advantagesof uniformity of
gauges.

8
(Contd.)

'2.
(a) .(i)

The x and y components in _.athree
dimensional flow are given by

u=x2+z2;v=y2+z2.
Find the simplestz-componentof velocity
that satises the continuity equation.
4

(ii) A vertical gap 23-5 mm wide of innite
extent contains oil of specific gravity

0-9andviscosity2-5N-s/m2.
A metalplate
1-5 In X 1-5 m X 1-5 mm weighing 50 N is
to be lifted through the gap at" a constant
speedof 0-1 m/sec.Estimatethe force required
to lift the plate.
'6
(b) A solid gravity dam has 10 numbers of waste
weir sluices, the width of each sluice being
4-0 m. The waste weir is designed for a high

ood discharge
of 100m3/sandtheweirconstant
is given as 1-76. It is proposedto increasethe
line storage of the reservoir behind the dam by

replacing the waste weir by a saddle siphon
spillwayhavingthe crestat all units beingat the
samelevel. The dischargecoefficient of this siphon

spillway is 0-64and the operatedheadfor all the
units is 7 m. Find the number of siphon units

necessaryto replacethe wasteweir and also find
the extra _linestorage obtained by remodelling of

the spillway.The HFL (high ood level) is the
samein caseof both types of spillway and the
priming depth for the saddlespillwayis 15 cm.
The area of water spread from HFL to about

1-5m below.HFL maybe takenas constantand

equalto 4-5millionm2.

E
"\-

l__0

(Contd.)

-J

(c) (i) A soil samplehas a porosity of 40%.
The specic gravity of solids is 2-7. Calculate
the (i)'
void ratio (ii) dry density (iii) unit
weight if the soil is 50% saturated and
(iv) unit weight- if the soil is, completely
saturated.

(ii)

5

A horizontal stratified deposit consists
of four layers each uniform
The permeabilities

in itself.

of the layers are

7-5=<l0&#39;4
cm/sec, 49><104 cm/sec,

13><10&#39;4
cm/secand 17><104
cm/secand
their thicknesses are 5 m, 4 In, 17 in and

6 m respectively. Find the effective average
permeabilities of the deposit in horizontal
and vertical

directions.

5

(d) Detennine the gradient from a point A to B from
the following observationsmade with a xed hair
tacheometcr tted

with an anallatic lens, the

constantof the instrumentbeing 100.
_

Readingon

Readingon Vertical

0-625
10

El

(Contd.)

3. (a) (i) A 10 cm diameterorice discharges
water at 45 litres per second under a head

of 2-75 In. A at plate-is held normal to the
jet just downstreamfrom the venacontracta ._

requiringa forceof 310N to resisttheimpact

of thejet. Find co-efficientsof contraction

Cc,velocityCVanddischarge
Cd.

4

1

(ii) A rectangular-gate.
of width 5 In and depth
1-5In is installedto controlthe dischargeas

shown
in Figurebelow.
TheendBishinged.
Determine
theforcenormalto thegateapplied
at A to open it.

Gate
JR

_
P

6

hinge. Gate: 5-0 m width

1-5
rndeptl1

(Contd.)

(b) In ne sand aquifer region, design a well to
get 10 litres/sec.yield, under depressionheadof
2-5 meters.

Value

of
A

in cu m./hr. per sq. metre

of the area may be taken as 0-60.
(6) (i)

10

A specimenof ne dry sand,whensubjected
to triaxial compression test,

failed at a

deviator stressof 400 l<N/m2.It failed with
a pronouncedfailure plane with an angle of
24° to the axis of the sample. Compute the
lateral pressureto which the specimenwould

have been subjected.
(ii)

5

An elevated structure with a total weight of
10,000 kN is supported on a tower with 4
legs. The legs rest on piers located at the

cornersof a square6 In on a side. What is
the vertical

stress increment

due to this

loading at a point 7 m beneath the centre of
the structure

?

(Assume
thattheloadbeapproximated
toa
_pointload acting at the cornersof a square

of 6m side).
(d) (i)

5

CurrentTruck-traic Volume(AADTT) for

a_Six-lane
freewayare shownin the table
below. A bituminous pavementwith a 20

yearsdesign
lifeis to bedesigned
according
to the Hveernmethod.Determinethe design
ESAL for lane-3 of this freeway, if it is
assumed that traffic-volumes

for each truck-

(Contd.)

classication will grow _linearlyby 25% over
the next 20 years.

Vehicle-type

Current traffic Volume
(AADTT)

2 axle Trucks
3 axle Trucks
4 axle

Trucks

5 axle Trucks
or

Assume

more

:

_(i) Lanedistribution
factorfor Lane-3is 0-80.
(ii)

ESAL constant as

Vehicle-type ESALConstant
2 axle Trucks
3 axle Trucks

4 axle Trucks
5 axle Trucks
or

more

5

(ii) What are advantagesof Traffic-Rotary? 5
4.

(a) (i)

In 1 : 20 model-of a spillway,the-velocity

anddischarge
are1-5n1/sec
and2-0m3/sec
respectively.
Findthecorresponding
velocity
and dischargein the prototype.
4
(Contd.)

(ii) An overow spillway is 50 m high. At the
designthe energyhead is 2-5 m over the
spillway. Find the sequentdepth and energy
loss in a hydraulic jump formed on a

horizontalapronat the toe of the spillway.

Neglectenergylossdueto ow overthe
spillway face. Assume co-efficient of

discharge
Cd = 0-735andvelocityat the
toe, before the jump can be approximated

as V = {2 g (totalhead)}"2.Whereg is
acceleration due to gravity.

6

(b) In a watershed
four non-recording
raingauges
have
been installed to-record rainfall data. The annual

rainfall record for one of the yearsis furnished
below

:

Location

site of

raingaugestation
Recorded

A

B

C

D

annual

rainfallin cm

100 120 140 $0

A_ssuming
anerrorof 10percentin theestimation
of meanrainfall find out the optimum numberof

non-recording
andrecording
raingauges
for this
watershed.

10

(c) A squarefooting locatedat a depth of 1-3 m
below the groundsurfacehasto carry a safeload
of 800

Find the size of the footing if the

desired factor of safety is 3. The soil has the

E

(Contd.)

following properties:

Void ratio, e = 0-55

Degree
of saturation,
Sr..=
50%
Specic gravity = 2-67
c = 3 1tN/tn

Fot¢=
3o°Nc=37«2,Nq=22«5,N;=
19«7s

(Bearing capacity
factors)

l

10

(d) (i) Whatarethevariousmethods
of tunnelling
in hardrocks?Writetheadvantages
of Moletunnelling method.

5&#39;

(ii) Determine
theturningradiusof thetaxiway
of a supersonic
transportaircraftwith a wheel-

baseof 30in andtreadofmainloadinggear
as 6-0 in. for a designturning speedof
50 kmph. Assume co-efficient of friction

betweentyre and pavementsurfaceas 0-13&#39;
and width of taxiway pavementas 22-5 in.
5

5. (a) (i) A metallicball of diameter5 mm drops
in a uid of density 800 kg/m3 and

viscosity
3 N-S/m2-.
Thespecicgravityof

metallic
ballis 9-0.Findtheterminal
fall

g

velocity
oftheball,andthedragexperienced

E.

by the ball.

4
(Contd.)

(ii)

A triangular charmel of apex angle 90° and
a rectangular channel of the same material
have the samebed slope. If the rectangular
channel has the depth of ow equal to the
width

of the channel and ow

areas in both

channels are the same, find the ratio of

discharges
in the rectangularandtriangular
channels respectively. Use Mannings
roughness equation for estimation of
velocity.
6
(13) (i)

A homogeneousearthdam42 m high is built
to storewater for irrigation water requirement
"with a eeboard

of

2 m. A horizontal

lter

of 30 m length is provided at its downstream

end."Thecoeicient of permeabilityof the

material
of thedamis given_as
2><1o&#39;3
cm/sec.
A ow net wasconstructedthroughthe body _.
of the dam and the following results were-&#39;
obtained

:

.

No.ofpotential
drops
=25
No. of ow

channels = 4

if
,

Calculate the seepageow per meter length
of the dam in -fps .
(ii)

The main canal from the headwork

6
of a dam

has been designed.to carry a dischargeof

40m3/s.
At acertain
location
along
thecourse
of the canala drop of 4-0In headis available.

E

(Cont_d.)

. It is proposed
to utilizethedropfor generation
of hydropower. Estimate how much kW

(kilowatt) of energy can be generated

assumingefciency of the machinery-used
as 75 per cent.

4&#39;

(c) Calculate
thesizeof a rectangular
tankto treat
2-0 million litres of water per day.The detention
pe_riodmay be assumedas 3 hours and overow

rate lessthan 40,000lit. per sq. m. &#39;of
the surface

areaper day.
(d)

(i)

10

What is Wet-dock ? Write the uses of Wet-

dockandexplainoperationof wet-dockusing
Lock and gate.
(ii)

Why is efficient ventilation systemrequired
in tunnelling operation ? What are the
requirementsof ventilationsystem? Explain
combination of blowing and exhausting
system of ventilation.

6.

(ii). (i)

5

5

A tube well of 15 cm diameter penetrates

fully an artesianaquifer 27 In thick.
Determine penneability of the aquifer if a

steadydischargeof 30 fps is obtainedfrom
the well under a drawdown

of 3-0 m at the

well face. Takeradius of inuence equal to
200 In.

6
(Contd.)

(ii)

Determine the amount of evapotranspiration

fromanareaif the__
totalrainfallprecipitated
during a storm is 10-0 mm. Given the
antecedentmoisture at the root in the
soil was 5-00 mm,- the loss of water due

to seepage 25 mm, losses due to
percolation2-00mm, surfacerun-o 3-00mm
and the

moisture

retained

in the

soil

is

1-00 mm.

4

(b) Explaintheprocess
of Anaerobicsludgedigestion.
Name the experiments to be performed in the
laboratory to determine the digestibility of

sludge.

10

(c) A footing, 2 m square, rests on 2; soft clay with
its base at a depth of 1-5 m from -groundsurface.
The clay stratum is 3-5 m thick and is underlain
by a rm sandstratum.The clay soil has following
properties :

wL= 30%,wn= 40%,GS= 270 t
¢»u
= 0°,cu= 0-5kg/cm?
It is known that the clay stratum is normally
consolidated.Using Skemptonsequationdetermine
the net safe bearing capacity of footing. Natural
water table is close to the ground surface. 10

(d) A National-highwaypassingthroughro11ingterIain
in heavy rainfall area has a horizontal curve of
radius 550 metre. Design the length of transition
(Contd.)

curve?assuming
designspeed
of 80krnph,normal

pavement
width= 7metre,
allowable
rateofchange
of centrifugal accelerationbetween 0-5-to 0-8 and

allowablerateof introduction-ofSuper-elevation
is 1 in 1_50.
(3) (i)

10

Determinethe maximumtime for _r_apid
closureof pipe60cmdiameter,
450milong
madeof steel(E = 2-07x10".N_/m2)
with
a wall thicknessof 1-25 cm. The pipe
carries a liquid of specic gravity 0-88
and bulk modulus K = 1-o3><1o9
N/m

owingat 1m3/sec.
E = Youngsmodulus
of steel.
(ii)

4

A centrifugalpump havingan impeller of
35 cm outsidediameterrotatesat 1050rpm.
The vanes are radial

at exit

and are

7-0 cm. wide. The velocity of radial

-ow throughthe impeller i_s3 m/se_c.__
The
velocity in the suctionand delivery pipes
are 25 rn/sec and 1-5 m/sec respectively.
Neglecting frictional "losses,determine the

height through which pump lifts and the
horse-powerof the pump.
8
(b) Describe photochemical oxidants. What are
the sources of photochemical oxidants and
how the detection and analysis for the same is
done

?

12

(Contd.)

_
&#39;~

I

(e) A retainingwall 4 In high, hasasmooth V_&#39;¬I&#39;lIiCal_
back. The backll has a. horizontal»surface in

level
with
the
top
ofthe
wall.
There
isa.-uniformly
distributed
surcharge
loadof 36kN/m2intensity
over the backll. The unit weight of backll soil

is &#39;18
kN/m3withangleof shearing
resistance,
(1:
of 30° and cohesion is zero. Determine the
-magnitudeand point of application of active
pressure per metre length of wall.

(a) (i)

16

A pipeline of length 26-5 km is used for
transmission

of

water.

If

the

100

kW

power is to be transmittedthrough the pipe

in whichwateris having490-SN/cmz
pressure
at inlet of thepipe,nd thediameter
of the pipe corresponding to _-maximum
efciency of transmission.Use headloss due

fLU 2
to friction

=-

2gd

where f = 0-026.

4

1.-

(ii) A pipelineof 0-6m diameteris 1-5km long.
To augmentthe dischargeanotherpipe-line
of the _samediameteris introducedparallel
to the rst in the secondhalf of the length.
Neglecting minor losses nd the "increase in

dischargeif f = 0-04 and head above the
outlet

is 30 In.

6

(Contd.)

I
3.. _. .

(b) (i)

The working life of dam built to store

irrigation requirementis expectedto be
100yrs. The spillway capacityis designed
to accommodate.the peak ood having a
return period of 500 yrs. Calculatethe risk
of failure of the dam.

(ii)

&#39;4

Show with the help of a neat sketch the

storage
capacities
allottedfor variouspurposes
in a multipurpose reservoir.

Briey explainwhat is meantby usefullife
of a reservoir and how it is estimated.

6

(c) Designa friction pile group to carry a load of
3000kN includingthe weight of the pile capat
a site wherethe soil is uniform clay to a depth
of 20 m underlainby rock. Averageunconned

compressive
strengthof clay is 70 RN/m2.The
clay maybe assumed"
to be of normalsensitivity
and normally loaded"with liquid limit of 60%.A

factor of safetyof 3 is requiredagainstshear
failure. (Assumelengthof pile as 10 m). 10
(d) Two straightsmeet at an angle of 137°.Due
to the position of a building, a curve is to"be
so chosen that it may pass near a point F,
50 metre on the bisector of the angle of
intersectionfrom the point of intersection.Find
the degreeof the curve and calculate how near it
passesto point F.
10