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indian Forest 537709 (Main)
Examination, 2024 JBNV-B-CVLE
CIVIL ENGINEERING
Paper - II
Time Allowed : Three Hours Maximum Marks : 200
Question Paper Specific Instructions
| Please read each of the following instructions carefully before attempting
questions 2
There are EIGHT questions divided in TWO sections.
Candidate has to attempt FIVE questions in all.
Questions No. 1 and 5 are compulsory and out of the remaining, any THREE are to be
attempted choosing at least ONE question from each section.
The number of marks carried by a question/part is indicated against it.
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 Question-cum-Answer (QCA) Booklet must be clearly struck off.
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 have their usual standard meanings.
Answers must be written in ENGLISH only.
JBNV-B-CVLE 1
SECTION A
౧1. (a) 9 703 of concrete mix is to be prepared using 40 bags of cement. As per
design, 800 litres of water is to be added. Determine the water — cement
ratio. If by mistake, the mason adds more than 800 litres water, how
does the increased water - cement ratio influence the properties of
concrete ?
00) | What are the various economic factors generally considered for selecting
equipment for a construction project ? Also discuss how versatility of the
equipment is advantageous in reducing ownership and operating cost of
equipment.
(০) What are the important features of ‘Resource Smoothing’ and
‘Resource Levelling’ approaches you understand to solve resource
allocation problem for a construction project ?
(प) For a plain cement concrete pavement, the coefficient of friction is 1-5,
the tensile strength of concrete is 1.2 kg/cm?, and the unit weight of
concrete is 2400 kg/m®. Determine the spacing of contraction joints in
pavement, which will be adopted here, as per Indian specifications. Also
determine the spacing between the expansion joints, if expansion joint
gap is 2-2 cm, maximum increase in temperature is expected to be 26°C
after the pavement construction, and thermal coefficient is 10 x 10
per °C.
(e) Levelling was carried out in an area, but while computing the values in
the table below, some of values became illegible due to sudden rain
drops. Find the missing values and check your answer. Also show
computations.
Station | BS (m) | IS (फ) FS (m) HI (m) RL (m) Remarks
1 x 134.600 | 132-385 BM
ਕਿ x 132-995
3 2-080 0-985 x x CP1
4 x 132-940
5 0-605 x x 134-440 CP2
| -6 | x 133-070
1 1.045 x
| 8 | x 132-360
JBNV-B-CVLE 2
Q2. (a)
It is proposed to use either equipment A or equipment B to operate an
earth pit for a construction project for a period of 6 years.
The data regarding equipment A and equipment B are given as follows :
4 year service
life and = 5000
each equipment
for replacement
will not be in
service for their
entire life
Equipment | Number | Initial cost | Operating | Salvage value | Service
required for each cost per life
for same | equipment | equipment
capacity per year
A 1 =2-5lakh | ₹ 1.1 1410) | Oattheendof | 6 years
project
8 ₹ 0-25 lakh | ₹ 0.3 lakh | 0 at the end ए | 4 years
(i)
(ii)
JBNV-B-CVLE
Assuming interest rate is 10 percent, compare present worth of
equipment A with all equipment B to be used and determine
which equipment, A or B, is to be preferred from present worth
point of view ? Assuming equipment B are replaced at the end of
4 years and the replacements will not be in service for their entire
useful life, their estimated salvage values (@ = 5000 for each
equipment B) must be included as a cash inflow at the end of
project in 6 years.
If equipment B are also available with an initial cost for each
equipment at ۴ 0-40 lakh and with a total extended service life of
5 years, determine whether it is to be preferred to use equipment
B with extended service life by comparing present worth as
obtained in case (i) above. Assume all other data as same as given
in case (i) above.
15
Q3.
(b)
(૦)
(a)
(b)
(০)
(i) A horizontal curve is to be designed in a hilly terrain for a
four-lane road with 3 m width of each lane. The deflection angle of
the curve is 50°, and the tangent length is 153 m. The point of
intersection is located at a chainage of 5 + 650 m. If the proposed
road has a coefficient of side friction as 0-082 and rate of
superelevation as 0-09 m/m, determine whether this road section
is appropriate for a design speed of 80 kmph; if not, redesign the
curve. Compute the chainages of Point of Curve (PC) and Point of
Tangency (PT).
(1) Write the importance of highway drainage as well as the
requirements of a good highway drainage system.
A vertical aerial photograph was taken with a camera of 15 cm focal
length and 23 cm format photograph. A straight length of highway AB
measures 16-25 on this photograph, while its corresponding distance on
a map at 1 : 25,000 scale is 6-5 cm. If the average elevation of the terrain
is 1200 m above mean sea level, determine the flying height of aircraft
at the time of photography. Also compute the ground area covered by
one single photograph.
From a survey station R, whole circle bearings of two stations P and Q,
which are inaccessible, were measured as 225700 and 153°26’,
respectively. The independent coordinates of stations P and Q are given
below :
Station Easting (m) Northing (m)
[ആ | 600 | 500
| ० | 700 450
Compute the independent coordinates of station R.
(i) What are the various applications of bulldozers in construction
works ? What are the important factors affecting the production
rate of bulldozers ?
ઊં) ` What are the advantages and disadvantages of fibre-reinforced
concrete over conventional concrete ?
For a speed of 60 kmph, an equilibrium cant is provided on a BG of 5°
curve. Calculate the value of equilibrium cant, and maximum
permissible speed on the track, allowing the maximum cant deficiency.
JBNV-B-CVLE 4
10
10
15
10
10
౧1. (5) ൮
(ii)
യ 0)
(ii)
What are the requirements of a material to be used as a damp
proofing material ? What are the various materials commonly
used in the buildings to prevent capillary rise of water for damp
proofing ?
Briefly discuss the criteria for deciding orientation of residential
buildings under hot arid zones of India.
The total cycle time for a given road intersection is 60 seconds; the
green time for the phase is 27 seconds and corresponding yellow
time is 4 seconds. The saturation headway is 2-4 seconds/vehicle,
the startup lost time is 2 seconds/phase, and the clearance lost
time is 1 second/phase. Calculate the capacity of intersection.
A linear relationship between average travel speed of vehicle
v (km/hr) and average density k (number of vehicles/km) for a
traffic stream on a road is given as v = 70 - 0-7 k. Determine the
capacity of vehicles on this road.
(60 | What are the advantages of using flat slab floors in modern buildings ?
What are the various factors to be considered in selecting a flooring type
for a ground floor ?
JBNV-B-CVLE
10
10
10
SECTION B
౧5. (a) <A stream of 150 litres/second is diverted from a canal and
105 litres/second is diverted to the field. An area of 3 hectares is
irrigated in 10 hours. Effective depth of root zone is 1-5 m. The runoff
loss in the field is 450 cu.m. The depth of water penetration varies
linearly from 2-0 m at the head end of the field to 1-5 m at the tail end.
Available moisture holding capacity of the soil is 20 cm per metre depth
of soil. Determine : 8
(1) Water Conveyance efficiency 01८);
(1) | Water Application efficiency (ಗ);
(iii) Water Storage efficiency (ಗ); and
(iv) Water Distribution efficiency (nq).
Irrigation has started at a moisture extraction level of 60% of the
available moisture.
(0) Discuss briefly, at least four types of spillways. 4x2=8
(୦) () The impounding reservoir has original storage capacity of
738 ha-m. The drainage area of reservoir is 80 10702, from which,
annual sediment discharges into the reservoir at the rate
0-1158 ha-m/km? of the drainage area. Assuming the average trap
efficiency as 80%, find the annual capacity loss of the reservoir.
Find percentage loss per decade. 4
(1) Estimate the fire demand of water for a city having a population
of 500000. Use Freeman formula, Kuichling formula, and
National Board of Fire Underwriters formula. What is the
average fire demand for Indian conditions ? 4
(d) Describe the sources and impacts of physical impurities in potable water
sources. 8
(e) Which inorganic gases cause significant air pollution ? Describe their
important characteristics and sources. 8
JBNV-B-CVLE 6
Q6.
(a)
(b)
(০)
An impervious floor of a weir on permeable soil is 16 m long and has
sheet piles at both the ends. The upstream pile is 4 m deep and the
downstream pile is 5 m deep. The weir creates a net head of 2-5 m.
Neglecting the thickness of the weir floor, calculate the uplift pressure
at the junction of the inner faces of the piles with the floor, by using
Khosla’s theory. Also, draw simple (upstream and downstream) profiles
with salient points.
Determine the magnitude of maximum compressive stress and
maximum shear stress that may develop under the reservoir empty
condition of a concrete dam shown in the figure below. Take unit weight
of concrete as 24 kN/m®. Reservoir is empty without tail race and no
sedimentation on the upstream face of the dam. Consider moments
about point A.
ey
=
4m
26m
।୧
60 m
XX XX
ந یہ 63 m ہپ سس سس
683
(B)
A continuous flow settling tank has an effective water depth of 3 m and
is 50 m long. Determine the flow velocity of water for removal of
0-03 mm particles at 25°C temperature. Take specific gravity of particles
as 2-65, kinematic viscosity of water as 0:01 cm?/s, 8 = 0-04 for
unigranular sand, and f = 0-025, friction factor.
JBNV-B-CVLE 7
15
15
10
Q7. (a) A town with a population of 200000 is to be supplied with water daily at
300 litres per head.
The variation of demand is given below :
6am 10 9 क्षण - 30% of total
Qamtol2noon - 15% of total
12noonto3pm - 15% of total
3 ما مم 6pm - 15% of total
6 pm to9 pm - 25% of total
Determine, by using the mass curve method, the capacity of the service
reservoir assuming pumping to be at a uniform rate and the pumping
period is to be from 6 am to 6 pm. Neglect fire demand. 15
(b) BOD tests were performed on 4 mL samples of a wastewater using
300 mL standard BOD bottles at different times. The results obtained
are shown in the table below :
Bottle No. | Initial DO in Incubation period Final DO
mg (days) (17/1)
1 9.2 0-5 8-3
2 9-2 1-0 7-3
3 9-2 15 66 |
4 9.2 2-0 6-1
5 92 3-0 5-1
| 6 | 9-2 5-0 4.0
Determine : 15
(i) The value of BOD rate constant per day.
Gi) The value of 5 day BOD.
(iii) The oxygen equivalent of organic matter present in wastewater at
the start of BOD reaction.
Use Thomas graphical method.
JBNV-B-CVLE ৪
(૦) The mass curve of rainfall in a storm of total duration 100 minutes is
given below :
Time (minutes) Cumulative rainfall (mm)
० એ | 0 |
20 | 6 |
40 22
6 | 33
| 80 | 37
100 40
0) Draw the hydrograph of the storm at 20 minutes time step;
(1) Plot the maximum-intensity-duration curve for the storm; and
(11) Plot the maximum-depth-duration curve for the storm. 10
Q8. (a) An extensive aquifer is known to have a groundwater flow N 30° E
direction. Three wells P, Q and R are drilled to tap these aquifers. Well
Q is East of P and well R is North of P. Estimate the elevation of water
table at well R, with the following data regarding these wells, when the
wells are not pumping. Also draw the layout of the wells. 10
॥ Ground surface elevation | Water table elevation
Distance
(0) Well (00) (m)
(above datum) (above datum)
| ए | 160-00 157-00
PQ = 800 159-00 156-50
PR = 2000 | ए | 158-00 ?
The canal is of clean gravel with coefficient of permeability (K) as
100 cm/second. Find the resultant velocity of flow.
JBNV-B-CVLE 9
(b)
(८)
The ordinates of 2-hour Unit Hydrograph (UH) are given below. Derive
the 6-hour UH for the same catchment. Also draw to a scale, the
resulting UH. 10
Time (hr) Ordinates of 2-UH
| ०0० | 0 |
2 40
4 100
७6७ | 50
8 | 10
10
Design a standard egg-shaped sewer pipe-section for a combined storm
water-sewage flow for a residential colony. Following data is given :
Area of colony : 30 hectares
Population : 20,000
Per capita water consumption : 200 /phd
Critical design rainfall intensity : 4 cm/hr
General available ground slope : 1 in 900
Coefficient of runoff for the area : 0-55
Manning’s coefficient for the pipe : 0-013
Assume :
(i) 80% of water consumed appears as sewage.
(ii) Peak sewage discharge = 3 times the average discharge.
Also draw neat sketch of the sewer section. 10
JBNV-B-CVLE 10
(0) Following is the composition of a hard water sample :
Free carbon dioxide = 4 mg/L
Alkalinity = 72 mg/L
Non-carbonate hardness = 100 mg/L
Total magnesium = 18 mg/L
Assume that it is possible to remove all but 38 mg/L of carbonate
hardness with lime and that the treated water is to have a total
hardness of 85 mg/L. Determine the amount of hydrated lime and soda
required for treatment per million litres of raw water. Take atomic mass
of : Ca = 40; Mg = 24, C = 12; 0 = 16; Na= 28, प = 1.
JBNV-B-CVLE 11
10

