
(Download) UPSC IAS Mains Exam Paper - 2017 : Civil Engineering
CIVIL ENGINEERING
(Paper 1)
Time Allowed : Three Hours
Maximum Marks : 250
QUESTION PAPER SPECIFIC INSTRUCTIONS
Please read each of the following instructions carefully before attempting
questions.
There are EIGHT questions divided in Two Sections and printed both in
HINDI and in ENGLISH.
Candidate has to attempt FIVE questions in all. Question Nos.
1 and 5 are compulsory and out of the remaining, any THREE are to be
attempted choosing at least ONE from each Section.
The number of marks carried by a question/part is indicated against it.
Answers must be written in the medium authorized in the Admission Certificate
which must be stated clearly on the cover of this Question-cum-Answer (OCA)
Booklet in the space provided. No marks will be given for answers written in a
medium other than the authorized one.
Wherever any assumptions are made for answering a question, they must be
clearly indicated.
Diagrams/Figures, wherever required, shall be drawn in the space provided for
answering the question itself.
Unless otherwise mentioned, symbols and notations carry their usual standard
meanings. Attempts of questions shall be counted in sequential order. Unless
struck off, attempt of a question shall be counted even if attempted partly. Any
page or portion of the page left blank in the Questioncum-Answer Booklet must be
clearly struck off.
SECTION "A"
1.(a) A vertical isosceles triangular gate with its vertex up has a base
width of 2 m and a height of 1.5 m. If the vertex of gate is 1 m below the free
water surface, find the total pressure force and the position of centre of
pressure.
(b) What are the advantages of High Strength Friction Grip bolts ? How the
load is transferred in High Strength Friction Grip bolts ? Explain with
sketches.
(c) An undisturbed soil at a borrow pit has a water content 12 per Cent, void
ratio 0.55 and specific gravity of solids 2.62. The soil from the borrow pit is
to be used for the construction of an embankment. The specifications for the
embankment require a dry density of 17.5 kN/m3 with a water content
of 18-5 per cent. Calculate the quantity of water in litres which is required to
be added to the borrow pit soil per m3 of finished embankment.
(d) A lever is loaded as shown in the above figure.
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(i) Calculate the moment of force at Point A.
(ii) Calculate the amount of horizontal force to be applied at B to produce the
same amount of moment of force as calculated above.
(iii) Calculate smallest amount of force to be applied at B, to produce the same
amount of moment of force as calculated in part (1).
(iv) Calculate the distance of point on lever, where 1:20 kN vertical force to
be applied to produce same amount of moment of force as calculated in part (i).
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Calculate bending moment and shear force and plot their variation for the
frame shown in the above figure.
2.(a) A 0.3 m diameter pipe carries water at a velocity of 24.4 m/s. At
points A and B, the pressures were measured 361 kPa and 288 kPa respectively.
The elevations of points
A and B were as 30.5m and 33.5m respectively. Find the loss of head between A
and B.
2.(b) A light weight building stands over a 10 m thick stratum of sand. Beneath
the sand stratum a clay layer of 5 m thick exists. The clay layer is underlain
by a rock stratum. The water table lies at a depth of 1-0 m below ground surface
and the sand above the water table is saturated with capillary rise. The sand
has a void ratio of 0.75 and sp. g. 2.65. During dry season, water is pumped out
from the sand stratum till the water table is lowered by 4.0 m and sand above
water table becomes dry. Calculate the number of days when the building settles
by 25 mm. Ignore settlement during pumping operation. Take properties of clay :
Void ratio = 0-60, Sp. gr. = 2.70, Liquid limit = 40%, Coefficient of
consolidation = 6x10-3 cm2/s.
2. (c) Details of a dog-legged stair for a building is shown in the above
figure. The floor to floor height is 30 m. The live load may be taken as 2.5 kN/m
thickness of the stair slab is 150 Tim. The rise and tread are 150 mm and 250 mm
respectively. Design and detail the typical flight. Use M-25 of concrete and
Fe-500 grade of steel. Use limit state method.
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3. (a) In a consolidated drained triaxial test (CD test) a specimen of
saturated sand failed under a deviator stress of 220 kPa when the cell pressure
was 100 kPa. Determine the shear strength parameters, the shear strength and the
maximum shear stress.
(b) An oil of dynamic viscosity 1-5 poise and relative density 0-9 flows through
a 3 cm diameter vertical pipe. Two pressure gauges are fixed 20 m apart. The
gauge A fixed at the top records 200 kPa and gauge B fixed at the bottom records
500 kPa. Find the direction of flow and the rate of flow.
(c) Calculate the vertical displacement of joint B of plane truss given in the
above figure by unit load method. All members of truss have constant
cross-sectional area and sattle material (Constalit A & E).
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4. (a) The above figure shows a two-layered backfill behind a 9.0 m high
retaining wall with a smooth vertical back. Draw the total active earth pressure
distribution diagram and find the point of application of the resultant earth
pressure.
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(b) Two moving loads, 300 kN cach and spaced 40 m apart, cross a 20-0 m long
simply supported girder from left to right as shown above. Calculate the
absolute maximum bending moment due to these moving loads.
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(c) A square hollow section is connected to the flange of ISMB 600 as shown
in the above figure. The bracket is subjected to symmetrical vertical and
horizontal load of each 50 kN. The size of SHS is 150x150x6 mm. Find the weld
size required for the connection.
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SECTION "B"
5. (a) A 1:50 scale spill-way model has discharge of 1:25 m/s. What is the
corresponding prototype discharge ? If a flood phenomenon takes 12 hours to
occur in the prototype, how long should it take in the model ?
(b) The design mix proportion of Cement: Fine agg. : Coarse agg. : Water for a
concrete mix of grade M-25 at Saturated Surface Dry (SSD) condition is l: 1:2:24
: (0-4 (by weight). Find out the revised mix proportion due to change of
material characteristics (Fine and Coarse agg.) for raining day before casting
at site.
Given : (i) Sp. gravity of Fine and Coarse agg. = 2.6 and 2.65 respectively.
(ii) Surface moisture (%) on Fine and Coarse agg. = 2.5 and 1.5 respectively.
How the durability factor is taken up during concrete mix design as per I.S.
code?
(c) A foundation trench is to be excavated for a large project in a site. The
soil investigation report shows the following details :
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It is observed that an open excavation is stable up to 5.75 m depth with the
existing water table. The excavation is to be made up to 8-5 m depth for which
water table is to be lowered. What are the initial and final depths of water
table ?
(d) Two bars of 50 mm dia are connected as shown in the above figure. Find
the maximum load P that can be applied. E = 2x10-5 MPa.
(e) Calculate the maximum shear stress in a hollow circular shaft having 300 mm
external diameter and 150 mm internal diameter. This shaft is subjected to a
twisting moment of 4 kN-m. If modultus of Rigidity G = 82 GN/m, calculate the
twist for a length of 20 times the external diameter of shaft.
6. (a) Three beam members are connected at the joint B as shown in the above
figure. Joint B is subjected to a clockwise moment of 100 KN-m. Calculate the
moment at A, C and D by Moment Distribution Method. All beam elements have
constant cross-sectional area and materials. (Constant I and E)
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(b)
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(c) A horizontal rectangular channel 4 m wide carries a discharge of 16 m/s.
Determine whether a jump may occur at an initial depth of 0:5 m or not.
Determine the sequent depth to this initial depth. Also find the energy loss in
this jump.
7. (a) A Pelton wheel turbine develops 5520 KW power under a head of 240 m at
an overall efficiency of 80%. The turbine is running at a speed of 200 r.p,m.
Find the unit discharge, unit power and unit speed assuming peripheral
coefficient as 0:46. If the head on the same turbine falls during summer season
to 150 m, find the discharge, power and speed for this head.
(b) An anchored sheetpile founded in a cohesive soil is to retain a sandy
backfill as shown in the above figure. Calculate the depth of embedment of the
sheet pile and the pull in the anchor.
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(c) Calculate maximum bending stress and shear stress at the fixed end of a
cantilever beam as shown in the above figure. Also sketch the variations of
bending stress and shear stress at fixed end. Beam has a uniform thickness of 50
mm. Beam has a depth of 200 mm at free end and 300 mm at fixed end.
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8. (a) A cantilever retaining wall is to be constructed to retain earth
embankment 3.1 m high above ground level. The unit weight of earth is 19 kN/m'
and its angle of repose is 35o. Dimensions of the wall are shown in the above
figure and the wall is safe against all stability check. Design the stem of the
wall using M-25 and Fe500. Detail the reinforcement in stein also. Use Limit
State Method. Given :
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(b) Air flows over a flat plate 1 m long at a velocity of 6 m/sec. Determine
(i) the boundary layer thickness at the end of the plate,
(ii) shear stress at the middle of the plate,
(iii) total drag per unit length on both sides of the plate. Take mass density
of air p = 1.226 kg/m3 and kinematic viscosity of air V = 0-15x10-4
m2/sec.
(c)
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