◆Types of road signals◆

(a) Manual Signals : Operated by a traffic police.

(b) Fixed time Signals:  These signals are set to repeat a cycle of sequence and phase of the cycle at regular intervals. Designed for peak time traffic requirements. Cause delay during off-peak hours.

(c) Traffic Actuated signals: Designed so that phase and cycle can bé‘ changed according to traffic demand. A yellow signal installed on main road warns the driver slow down.

(d)Pedestrian Signals: For Pedestrian control. One signal is erected on each side of crossing.

‘ It has only two colours -Red and Green.

MORTAR VS CONCRETE

◆MORTAR VS CONCRETE◆

●CONCRETE:
Concrete is a composite material produced from a mixture of sand, cement, aggregates and water in required proportions.

●MORTAR:
Mortar is made from a mixture of cement, sand, and water.

●DIFFERENCE BETWEEN MORTAR AND CONCRETE:

1. Concrete is a mixture of cement, sand, aggregates and water, on the other hand, mortar is made from cement, sand, and water.

2. Concrete is much stronger than mortar.

3. Mortar is less durable than concrete.

4. The water-cement ratio is higher in mortar, but the main aim of concrete is to keep the water-cement ratio as  minimum as possible.

5. Mortar is a good binding material and it is mostly used to bind the bricks together. Due to greater strength and durability concrete is used in all type of construction works such as buildings, bridges, roads etc.

6. Concrete gives a long outcome but mortar has to be replaced in every 20 – 30 years

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◆ Classification based on methods of Tunnel 

Construction

a) Cut and Cover Tunnels. These are built by 

excavating a trench, constructing the concrete 

structures in the trench and covering the soil. The 

tunnel may be constructed in place or by using precast sections.

b) Bored or Mined Tunnels. These are built without excavating the ground. These tunnels are named 

according to the material through which they pass.

c) Rock tunnels. These are excavated through the rock by drilling and blasting, by mechanized excavators in softer rocks or by using ‘Tunnel Boring Machines’ (TBMs). Sequential Excavation Method (SEM) is also used, in new tunnels these days.

d) Soft Ground Tunnel. These are excavated through soil using shield or by TBMs which balance earth pressure or by mining methods.

e) Immersed Tunnels. These are made from very large precast concrete or concrete filled steel elements that are fabricated in the dry, floated to the site, placed in prepared trench below water and connected to previous elements and then covered up with backfill.

f) Jacked Box Tunnels. Are pre-fabricated box 

structure jacked horizontally through the soil using methods to reduce surface friction. Jack tunnels are used where surface must not be distributed like beneath a runway, or embankment.

◆ Classification based on position or alignment

a) Saddle and Base Tunnels. To minimize the length of tunnel the track is led through valley as long as natural slope of the valley does not become steeper than ruling gradient of the route. Such tunnels are called ‘Saddle and Base’ tunnels.

b) Spiral Tunnels. In narrow valleys, the additional 

length for minimum permissible radius is obtained by forming a loop into the interior of mountain, such tunnels are called ‘Spiral Tunnels’.

c) Off Spur Tunnels. Tunnels that are made to short-cut minor local obstacles. They are very short in length.

d) Slope Tunnels. To ensure safe operation and 

protection to railway and highway routes in steep 

mountains, ‘Slope Tunnels’ are used. They are also constructed from economic point of view.

CLASSIFICATION OF TUNNELS

◆Classification based on the purpose

Tunnels on this basis can be classified as:
i) Traffic-Tunnels. For carrying traffic such as

a) Railways tunnels.
b) Highway tunnels.
c) Pedestrian tunnels.
d) Navigation tunnels.
e) Subway tunnels etc.

ii) Conveyance tunnels. For conveying utilities such as

a) Hydro-electric power tunnels.
b) Water supply tunnels.
c) Tunnels for intake & conduit of public utilities.
d) Sewer-tunnels
e) Transporting tunnel in industrial plant etc.

◆Classification based on type of ground
Such as

a) Tunnels in hard rock.
b) Tunnels in loose sand.
c) Tunnels in quick sand.
d) Open-cut tunnels.
e) Submarine tunnels or tunnels in river bed etc.


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Useful Notes on Cement

●Useful Notes on Cement●

◆ 1 Bag of Cement = 50kg

◆ 20 Bags of cement = 1000kg

◆ 1 Bag of Cement = 34.7 Litres

◆ 1 Bag of cement = 0.0347 Cublc meter

◆ 1 Cubic feet of Cement = 40 kg

◆ 1 Cubic meter of Cement = 28.8 Bags

◆ Density of Loose Cement = 1440 kg/m

◆Specific Gravity of Cement = 3.15

◆ Grades of Cement = 33,43, 53

Where, 33, 43, 53 are Characteristic Compressive Strength of Cement In N/mm2

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Difference between the One-way slab and Two way slab.

Difference between the One-way slab and Two way slab.

ONE WAY SLAB:

1) One way slab is supported by beams in only 2 sides.

2) The ratio of longer span panel (L) to shorter span panel (B) is equal
or greater than 2. Thus, L/B >= 2.

3) Main reinforcement is provided in only one direction for one way slabs.

4) One way slabs will behave in the same manner as a support beam.

TWO WAY SLAB:

1) Two way slab is supported by beams in all four sides.

2) The ratio of longer span panel (L) to shorter span panel (B) is less than 2     Thus, L/B < 2.

3) Main reinforcement is provided in both the directions for two way slabs.

4) Two way slabs is evenly distributed and will reduce bending and shifting.

These are the difference between one way slab and two way slab.

Fire demand can be calculated by using following formulae

#Environmentalengg @civilbhai

🎯 Fire demand can be calculated by using following formulae

🔹 National Board of Fire Under Writers Formula

Q = 4640 √p (1 - 0.01√p)

🔹 Freeman's formula

Q = 1135.5 [(p/10) + 10]

🔹 Kuichling's Formula

Q = 3182 √p

🔹 Buston's Formula

Q = 5663√p

Where, Q = quantity of water required ( litres/min.)
P = population of the town in thousands
👉 @civilbhai

REQUIREMENTS OF A GOOD ROAD AGGREGATE

REQUIREMENTS OF A GOOD ROAD AGGREGATE 

Following are the desirable properties or requirements of a good road aggregate: 

(1) Adhesion with bitumen: The aggregates which are to be used for the bituminous pavements should have less affinity with water as compared with the bituminous material. If this quality is absent in the aggregate, it will lead to the separation of bituminous coating in the presence of water.

(2) Cementation: The binding quality of the road aggregate depends on its ability to form its own binding material under traffic so as to make the rough broken stone pieces grip together to resist displacement by traffic. This quality is especially required in the case of water-bound macadam construction where the binding action of the surface layer is imparted by the stone dust and the film of water.

(3) Durability: The durability of an aggregate indicates its resistance to the action of weather and is largely dependent upon its petrological composition. The road metal is subjected to the oxidizing influence of air and rain water, it is therefore desirable that the road aggregate should possess sufficient soundness to resist the action of weather and age so that the life of road made
 with it may be prolonged.

(4) Hardness: The road aggregates should be reasonably hard to offer resistance to the actions of abrasion and attrition. The aggregates are always subjected to the constant rubbing action with the moving traffic. It is known as abrasion and it will be increased due to the presence of abrasive material like sand between the exposed top road surface and the tyres of moving vehicles.

(5) Shape: The shapes of aggregates may be rounded, cubical, angular, flaky or elongated. The flaky and elongated particles possess less strength and durability and their use in the road construction should be avoided as far as possible. The rounded particles are preferred in cement Concrete roads. But they are unsuitable in W.B.M. construction, bituminous construction and in granular base course because their stability due to interlocking is less. The angular particles are preferred in such types of construction.

(6) Strength: The road aggregates should be sufficiently strong to withstand the stresses developed due to the wheel loads of the traffic. This property is especially desirable for the road aggregates which are to be used in top layers of the pavements. Thus, the wearing course of road should be composed of aggregates which possess enough strength in addition to enough resistance to crushing.

(7) Toughness: The toughness of an aggregate is that property which enables the aggregate to resist fracture when struck with a hammer and it is necessary in a road metal to withstand the impact blows caused by traffic. It is desirable that the road aggregate is reasonably tough.

TYPES OF ROAD AGGREGATES

TYPES OF ROAD AGGREGATES

The raw material which is used as road aggregates can be classified in the following two categories:

(1) Natural aggregates: The term natural aggregate is used

loosely to designate aggregates which need only be removed from their natural deposits as unconsolidated sediments. The aggregates obtained from such deposits are called gravel and sand while those produced from rock, boulders or cobble stones are known as cmshed stone. Thus, the natural aggregates can be divided into the following three types:

a Crushed rock aggregate b. Gravel c. Sand

(2) Artificial aggregates: The blast furnace slag is perhaps the

only artificially prepared aggregate which is used in the road construction it is obtained as a by-product in the manufacture of steel If slag is specially manufactured under controlled conditions, it can certainly prove to be an excellent road aggregate of uniform quality.

Types of Pipes

◆Types of Pipes◆

1) Metallic Pipes
• cast iron pipes are used for distributary mains.
• Cast iron pipes are also known as spun Iron pipes.

Steel Pipes
• Steel pipes are provided for water mains passing through bridges.
• These pipes are mostly used for carrying raw water only.

Wrought Iron pipes
These are used for water distribution inside the buildings for service connection.Copper Pipes
• Copper pipes are used to carry acidic & alkaline water because copper is highly resistant to acid & alkalis.
• Copper pipes are used to carry hot water.

Zinc Pipes
• These are the iron pipes cover by zinc coating & are known as Gal vanished iron pipes.
• These pipes are not used for acidic & alkaline water.

Lead Pipes
• These pipes are used for sanitary plumbing.
• These pipes are never used for drinking water purpose.

2) Non- Metallic Pipes

RCC & Pre-stressed pipes
These pipes are used for distributary mains.

PVC Pipes ( Polyvinyl chloride Pipes)
These pipes are lighter in weight& can be used for plumbing in buildings.

Asbestos Cement Pipes
These pipes are highly resistant to corrosion& can be used for acidic water only.

Sources of Water

◆Sources of Water◆

1) Surface Sources
• The major source of surface water is rainfall.
• It contains dissolved & suspended impurities.
• e.g. Rivers, canals, lakes, ponds, spring etc.
• River is the purest source among surface sources due to self-cleaning nature.
• River water contains highly suspended impurities only.

2) Sub- Surface Sources
• Major source is Underground water below water table.
• It contains dissolved impurities (dissolved gases & minerals.)
• e.g. wells, infiltration galleries & infiltration wells.

• Infiltration Galleries.

➔These are the large tunnels placed along bank of river.
→These are placed at depth of 3 m to 5m below ground surface.
→It consist of perforated pipes that collect the seepage water & transfer to galleries.

Infiltration Wells
➔ These are the open wells which are placed at suitable interval along the bank of river.
➔ These are subjected to atmospheric pressure.

Intakes Structures
The structures which are used to collect surface waters from their sources are known as Intake structures.

Types of Intake
1) On the basis of Use
i) River Intake
ii) Canal Intake
iii) Lake Intake
2) On the basis of function/Operation
i) Submerged
ii) Tower

Well
A water well is a vertical hole excavated below the ground surface to excavate ground water.

Open Well
• The well in which flowing velocity of water is less than critical velocity is known as open well.
• The critical velocity is the max permissible velocity above which the movement of soil particles take place along with water.
• Max. discharge of open well is 5 liters per second (5lps)

Shallow Well
• It is a type of open well that can be excavated up to certain depth of first
permeable layer.

Deep Well
• This well is excavated up to complete depth of first permeable layer below ground surface.
• The discharge of deep well is always more than discharge of shallow well.

Tube Wells
• It is a long-perforated pipe i.e. dug below the ground surface up to no. of permeable & impermeable layers.
• Max. value of discharge is 50 lps

Miscellaneous Tratment

◆Miscellaneous Tratment◆

i) Use of Activated Carbon [add at time of coagulation& filtration.]

• Activated Carbon is a strong oxidizing compound which has surface pores.

• These pores adsorb the impurities present in water.

• It can remove odour, colour, excess fluorides, excess chlorides, organic matter, microorganisms etc.

• It can’t remove suspended solids & Turbidity of water.

• Optimum Dose = 5-20 mg/l

• If addition of Activated carbon is done during coagulation& after filtration

simultaneously, it is known, as Split Carbonation.

ii) Use of Cuso4

• It is used to prevent algae growth in water.

• It is added to the water just before the distribution.

• Optimum dose = 0.5- 0.6 mg/l.

iii) Fluoridation

• The process of addition of fluorides in water is known as Fluoridation.

• It is done by sodium Fluorides (Na2F), Sodium Fluoride sulphates (Na2FSo4) & sodium silica Fluorides.

• If the Fluoride in water is more than permissible limit, the removal of fluoride is done. This process is known as Defluorination.

• It is done by activated Carbon, Thiosulphide& bone charcoal, Lime.

iv) De- salination

• The process of removal of salts from water is known as Desalination.

• It can be done by Freezing and Reverse Osmosis,electrolytic methods ,evaporation

• Freezing is done on small scale.

• Reverse Osmosis is the process of movement of water form high concentrated to low concentrated water using semi-permeable membrane.

• Reverse Osmosis is done on commercial scale.

Softening of Water

◆Softening of Water◆

1)Lime Soda Method/Clark’s Process

• Lime removes all the carbonate hardness.

• Lime converts non-carbonate hardness of magnesium into non-carbonate harness of calcium.

• Soda removes non carbonate hardness of calcium

• These reactions take place when pH of water is more than 9.
( ppt of CaCO3 formed at pH>9-9.5 & ppt of mg(OH)2 when pH> 11 . PH INCREASES
ARTFICIALLY BY ADDING LIME)

• This methodremoves all the carbonate & non carbonate hardness both.

• this method decreases the corrosion problems in pipes due to increase in alkalinity of water, reduce hardness.

• This This method removes all the microorganisms present in water due to high
alkalinity.

2) Zeolite Process/Permitut Method/ Base Exchange Process

• This method can produce zero hardness in water.
It can’t produce Na2Z if Fe and Mn present in solution

• In this method, no sludge formation takes place.

• This method is not used for highly turbid water & colored water (costlier)

3) De-mineralization Process

• Resins are the polymeric compounds which are used to remove hardness from water.

• Acidic resins & basic resins are used for treatment.

• This method produces zero harness& almost zero sludge formation.

• This method can improve taste of water & almost zero sludge formation.

Measurement/Test for Residual Chlorine

◆Measurement/Test for Residual Chlorine◆

1) Starch Iodide Test

• Water sample is mixed with potassium iodide (KT).

• If blue colour complex is formed, it indicates presence of Residual chlorine.

• This blue solution is titrated with sodium Thiosulphide.

Residual chlorine = 0.3456 × Volume of sodium Thiosulphide solution used to convert blue colored complex into colorless

• This test is used for colored water only.

2) Orthotolidine Test

• The sample is mixed with orthotolidine.

• If colour of sample changes within 5 sec, its indications presence of free
chlorine.

• If colour of sample changes within 5 min, it indicates presence of combined
chlorine.

• This test is not used for colored water.

Types of Chlorination

◆Types of Chlorination◆

1) Plain Chlorination

• If Turbidity of water is less than 10NTU or 20-30 mg/l. only this disinfection is provided in the form of chlorination which is known as plain chlorination.

• The dose of chorine = 0.5 mg/l (act as residual chlorine)

2) Pre chlorination

• When organic impurities in water are very high, then chlorination is provided on or before filtration.

• Does of chlorine = 5-10mg/l. at coagulation
 = .1- .5mg/l at filtration.

3) Post Chlorination

When chlorination is provided after filtration, when water is provided pre-chlorination the amount of chlorine should be such that the residual chlorine
must be 0.2mg/l with 10 min. contact period.

4) Double Chlorination

The Combination of pre & post chlorination is known as Double chlorination.

5) Super Chlorination

• When excess chlorine (5-50 mg/l) is added for disinfection, it is known as super chlorination. It is done for epidemic water→ Residual Cl → 1-2 mg/l.

• Excess chlorine after disinfection is removed out of water such that residual chlorine should be 0.2 – 0.5 mg/l. It is known as DE chlorination.

• It can be done by adding Activated carbon or sodium thiosulphate.

Types of Chlorine Compounds

◆Types of Chlorine Compounds◆

1) Free chlorine (Cl2)

• It is used in the form of liquids.
• If temp. of water is less than 100 C, liquid chlorine converts into solid crystals
and settles down in water.
• If temp of water is more than 920C, it is converted into gaseous form which is
explosive in nature.
• The optimum temp range for use is 35-480C.
• Free chlorine does not form any sludge.

2) BleachingPowder (CaOCl2)- Calcium oxy chloride.

• Due to bleaching powder, hypochlorous acid is formed.
• It is used for treatment of water in swimming pools.
• Not used for treatment of water in pipes as it causing choking of pipes

v) Ultra violet rays :

• Very costly technique and is an effective method for the disinfection of water.

• No residual effect is available for protection against recontamination.

• Adopted for water supply installations of private Buildings. Institutions, Treating small quantities of water in hospitals. dispensarics for surgical use. Swimming pools

vi) Potassium Permanganatc :

• For disinfecting well water supplies which are generally contaminated with lesser amounts of bacteria.

• Can remove 100 % organisms causing cholera.

• it also oxidizes organic matter.

vii) Silver or Electro-Katadyn Process:

• Removes algae also and takes care of future  pollution. it is costly.

viii) Chlorination :

•Universally adopted for public water supplies because it is capable of providing residual disinfecting effects for long periods. It satistics all the requirements of an ideal disinfectant.

• It takes carc‘ of any possible future contamination. ( i.c it prevents rccontamination)

• only disadvantage is it impact bad taste.

•The addition of chlorine does not produce any significant change In the pH.

• value of the natural waters.

•Chlorination is not effective if the water is alkaline.

Disinfection

◆Disinfection◆

Disinfection : It is the process of killing pathogenic bacteria.

Methods:

i) Boiling of water :

•Most effective method of disinfection of water.

•cannot be used for huge quantities of public water supplies.

•cannot take care of the future possible contaminations.

•used only for Domestic purposes emergencies.

ii) Treatment with excess limes.

• Effectively kills the bacteria. but cannot safe guard the future pollution.

• Enough lime is added to water to raise, its  pH value to 9.5 or more, thereby most of the bacteria will be killed.

• Recarbonation is necessary. The process of removal of excess lime before. it is supplied to public is know as Recarbonation.

iii) Ozone.

• Ozone is a more powerful disinfectant than Chlorine.

• Ozone Is more costly than chlorine.

• Does not provide residual protection against  rccontnminalion.

• Cannot be stored.

• Used for disinfection of water on a small scale such as for swimming pool waters.

Iv) Iodine and Bromine pills.

• Compared to chlorine . iodine provides longer lasting pmtcctiun against pathogens and reduced offensive tastes and odours.

• used for water supply for army troops, private plants. swimming pools.

• Cannot be uscd for public water supply as it is costly.

Continue....

Objectives of Treatment of Water

◆Objectives of Treatment of Water◆

To make water odour & taste free.

To make it colourless.

To make the water safe & sparkling for drinking & domestic purposes.

To remove dissolved gases & turbidity.

To make it free from all objectionable impurities present in suspension, colloidal or dissolved form to remove harmful bacteria.

To remove hardness.

To make water suitable for a wide variety of industrial purposes.

Water Requirements for Buildings Other than Residences

Water Requirements for Buildings Other than Residences

i) Factories where bath rooms are required to be provided = 45 per head

ii) Factories where no bath rooms are required to be provided = 30 per head 

iii) Hospital ( including laundry ) :

a) Number of beds not exceeding 100 = 340 per head

b) Number of beds exceeding 100 = 450 per head

iv) Nurses’ homes and medical quarters = 135 per head

v) Hostels = 135 per head

vi) Hotel = 180 per head

vii: Offices = 45 per head

viii) Restaurants = 70 per seat

ix) Cinemas, concert halls and theatres = 15 per seat

x) Schools:

a) Day schools = 45 per head
b) Boarding schools = 135 per head

WATER SUPPLY REQUIREMENTS

 WATER SUPPLY REQUIREMENTS

Water Supply for Residences
A minimum of 70 to 100 litres per head per day
may be considered adequate for domestic
needs of urban communities, apart from non
domestic needs as flushing requirements. As a general rule the following rates per capita
per day may be considered minimum for
domestic and non domestic needs:

1) For communities with population up to 20 000 and without flushing system

a) water supply through 40 lphd ( Min ) standpost
b) water supply through 70 to 100 lphd house service connection

2) For communities with population 20 000 to 100 to 150 lphd 100,000 together with full flushing system

3) For communities with populationabove 100 000 150 to 200 lphd together with full flushing system.

NOTE - The value of water supply given as 150 to
200 litres ner head ner day may be reduced to 135
litres per head per hay fo; houses for Lower Income Groups ( LIG ) and Economically Weaker Section of Society ( EWS ), depending upon prevailing conditions.

Out of the 150 to 200 litres per head per day, 45 litres per head per day may be taken for flushing requirements and the remaining quantity for other domestic purposes.

◆Quality of water◆

• Pure Water: It is a chemical compound(H20) 

• Potable Water:Water which is fit for drinking. 

• Palatable Water: Water which is aesthetically looking good.

• Wholesome Water: Chemically may not be pure but doesn't contain anything harmful to human beings. 

• Polluted Water: It contains undesirable substances rendering it unfit for drinking and domestic use. 

• Contaminated Water: It contains pathogenic bacteria and unfit for drinking.

• Mineral water: It contains useful minerals viz. Calcium, Magnesium and Iron in required proportion.

What is Honeycomb

What is Honeycomb?

Honeycombs are hollow spaces and cavities left in concrete mass on the surface or inside the mass where concrete could not reach.
These look like honey bees nest.

Causes of honeycomb in Concrete:

1 .Insufficient compaction to concrete.
2 .Less cover to reinforcement bars.
3 .Improper Workability in concrete
4 .Concrete already set before placing .
5 .High concrete free fall while pouring
6 .Form work not watertight/rigid.
7 .More coarse aggrgegates than designed mix proportions and over sized aggregates.
8 .Improper placement of bars at column and beam junction.
9 .Addition of more water than designed at site for achieving workability.
10 .Steel congestion not allowing concrete flow to all corner.

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Question No. 41
Which of the following statements is incorrect?
(A) Error due to refraction may not be completely eliminated by reciprocal levelling
(B) Tilting levels are commonly used for precision work
(C) The last reading of levelling is always a foresight
(D) All of the above statements are incorrect
Answer: Option D

Question No. 42
In levelling operation,
(A) The first sight on any change point is a back sight
(B) The second sight on any change point is a fore sight
(C) The line commences with a fore sight and closes with a back sight
(D) The line commences with a back sight and closes with a foresight
Answer: Option D

Question No. 43
The length of a traverse leg may be obtained by multiplying the latitude and
(A) Secant of its reduced bearing
(B) Sine of its reduced bearing
(C) Cosine of its reduced bearing
(D) Tangent of its reduced bearing
Answer: Option A

Question No. 44
While working on a plane table, the correct rule is:
(A) Draw continuous lines from all instrument stations
(B) Draw short rays sufficient to contain the points sought
(C) Intersection should be obtained by actually drawing second rays
(D) Take maximum number of sights as possible from each station to distant objects
Answer: Option B

Question No. 45
The vertical angle between longitudinal axis of a freely suspended magnetic needle and a
horizontal line at its pivot, is known
(A) Declination
(B) Azimuth
(C) Dip
(D) Bearing
Answer: Option C

Question No. 46
In the cross-section method of indirect contouring, the spacing of cross-sections depends upon
(i) Contour interval
(ii) Scale of plan
(iii)Characteristics of ground
The correct answer is
(A) Only (i)
(B) (i) and (ii)
(C) (ii) and (iii)
(D) (i), (ii) and (iii)
Answer: Option D

Question No. 47
Transition curves are introduced at either end of a circular curve, to obtain
(A) Gradually decrease of curvature from zero at the tangent point to the specified quantity at
the junction of the transition curve with main curve
(B) Gradual increase of super-elevation from zero at the tangent point to the specified amount
at the junction of the transition curve with main curve
(C) Gradual change of gradient from zero at the tangent point to the specified amount at the
junction of the transition curve with main curve
(D) None of these
Answer: Option B

Question No. 49
Tilt of the staff in stadia tacheometry increases the intercept if it is
(A) Away from the telescope pointing down hill
(B) Towards the telescope pointing up-hill
(C) Away from the telescope pointing up-hill
(D) None of these
Answer: Option C

Question No. 31
Subtense bar is an instrument used for
(A) Levelling
(B) Measurement of horizontal distances in plane areas
(C) Measurement of horizontal distances in undulated areas
(D) Measurement of angles
Answer: Option C

Question No. 32
Volume of the earth workmay be calculated by
(A) Mean areas
(B) End areas
(C) Trapezoidal
(D) All the above
Answer: Option D

Question No. 34
Pick up the correct statement fromthe following:
(A) The directions of plumb lines suspended at different points in a survey are not strictly
parallel
(B) In surveys of small extent, the effect of curvature may be ignored and the level surface of
the earth is assumed as horizontal
(C) In surveys of large extent, the effect of curvature of the earth must be considered
(D) All the above
Answer: Option D

Question No. 35
In levelling operation
(A) If second reading is more than first, it represents a rise
(B) If first reading is more than second, it represents a rise
(C) If first reading is less than second, it represents a fall
(D) Both (b) and (c)
Answer: Option D

Question No. 36
Over-turning of vehicles on a curve can be avoided by using
(A) Compound curve
(B) Vertical curve
(C) Reverse curve
(D) Transition curve
Answer: Option D

Question No. 37
Which of the following introduces an error of about 1 in 1000 if 20mchain is used?
(A) Length of chain 20 mm wrong
(B) One end of the chain 0.9 m off the line
(C) One end of chain 0.9 m higher than the other
(D) All the above
Answer: Option D

Question No. 38
Chain surveying is well adopted for
(A) Small areas in open ground
(B) Small areas with crowded details
(C) Large areas with simple details
(D) Large areas with difficult details
Answer: Option A

Question No. 39
Two contour lines, having the same elevation
(A) Cannot cross each other
(B) Can cross each other
(C) Cannot unite together
(D) Can unite together
Answer: Option D

Question No. 21
Detailed plotting is generally done by
(A) Radiation
(B) Traversing
(C) Resection
(D) All of the above
Answer: Option A

Question No. 22
If the smallest division of a vernier is longer than the smallest division of its primary scale, the
vernier is known as
(A) Direct vernier
(B) Double vernier
(C) Retrograde vernier
(D) Simple vernier
Answer: Option C

Question No. 23
Themethod of reversal
(A) Is usually directed to examine whether a certain part is truly parallel or perpendicular to
another
(B) Makes the erroneous relationship between parts evident
(C) Both (a) and (b)
(D) Neither (a) nor (b)
Answer: Option C

Question No. 24
The line normal to the plumb line is known as
(A) Horizontal line
(B) Level line
(C) Datum line
(D) Vertical line
Answer: Option B

Question No. 25
In levelling operation
(A) When the instrument is being shifted, the staff must not be moved
(B) When the staff is being carried forward, the instrument must remain stationary
(C) Both (a) and (b)
(D) Neither (a) nor (b)
Answer: Option C

Question No. 26
The two point problem and three point problem are methods of
(A) Resection
(B) Orientation
(C) Traversing
(D) Resection and orientation
Answer: Option D

Question No. 27
Ramsden eye-piece consists of
(A) Two convex lenses short distance apart
(B) Two concave lenses short distance apart
(C) One convex lens and one concave lens short distance apart
(D) Two Plano-convex lenses short distance apart, with the convex surfaces facing each other
Answer: Option D

Question No. 28
The line of sight is kept as high above ground surface as possible to minimise the error in the
observed angles due to
(A) Shimmering
(B) Horizontal refraction
(C) Vertical refraction
(D) Both shimmering and horizontal refraction
Answer: Option D

Question No. 30
The desired sensitivity of a bubble tube with 2 mm divisions is 30". The radius of the bubble tube
should be
(A) 13.75 m
(B) 3.44 m
(C) 1375 m
(D) None of these
Answer: Option A

FORMWORK

◆FORMWORK◆

Formwork is a temporary structure. There are two types of formwork shuttering and centering. The type of formwork, which is not in direct contact of structure is called shuttering.

●The part of formwork, which is used to support the shuttering is called centering.

●Stripping time may be reduced to 40% in the case of rapid hardening cement Shoring is the construction of a temporary structure to support temporarily on unsafe structure.

●The process of placing a New foundation under an existing one/strengthening an existing foundation is called underpinning of foundations.

●Cost of formwork/shuttering may be upto (20-25)% of the cost of structure in the building work Trestle scaffolding is used for painting and repair work inside the room up to a height of 15 meters

(a) Vertical formwork to beams, columns, walls =16-24 h

(b) Soffit formwork to slabs (props to be refixed immediately after removal of formwork) =3 days 

(c) Soffit formwork to beams (Props to be refixed immediately after removal of formwork) =7 days

(d) Props to slabs
(i) Spanning up to 4.5m =7 days
(ii) Spanning over 4.5m =14 days

(e) Props to beams and arches

(i) Spanning up to 6 m =14 days

(ii) Spanning over 6 m =21 days

●●●●●●●●●●●●●●●●●●●●●●

🅙🅞🅘🅝 Telegram @civilbhai

Question No. 11

The smaller horizontal angle between the true meridian and a survey line, is known
(A) Declination
(B) Bearing
(C) Azimuth
(D) Dip
Answer: Option C

Question No. 12

Contour interval is
(A) The vertical distance between two consecutive contours
(B) The horizontal distance between two consecutive contours
(C) The vertical distance between two points on same contour
(D) The horizontal distance between two points on same contour
Answer: Option A

Question No. 13

Check lines (or proof lines) in Chain Surveying, are essentially required
(A) To plot the chain lines
(B) To plot the offsets
(C) To indicate the accuracy of the survey work
(D) To increase the out-turn
Answer: Option C

Question No. 14

After fixing the plane table to the tripod, the main operations which are needed at each plane
table station are
(i) Levelling
(ii) Orientation
(iii)Centering
The correct sequence of these operations is
(A) (i), (ii), (iii)
(B) (i), (iii), (ii)
(C) (iii), (i), (ii)
(D) (ii), (iii), (i)
Answer: Option B

Question No. 15

There are two stations A and B. Which of the following statementsis correct?
(A) TheforebearingofABisAB
(B) ThebackbearingofABisBA
(C) The fore and back bearings of ABdiffer by 180°
(D) All the above
Answer: Option D

Question No. 16

The Random errorstend to accumulate proportionally to
(A) Numbers of operationsinvolved
(B) Reciprocal of operationsinvolved
(C) Square root of the number of operation involved
(D) Cube root of the number of operation involved
Answer: Option C

Question No. 17

In direct method of contouring, the process of locating or identifying pointslying on a contouris
called
(A) Ranging
(B) Centring
(C) Horizontal control
(D) Vertical control
Answer: Option D

Question No. 18

Question No. 19

Pick up the incorrectstatement from the following:
(A) While measuring a distance with a tape of length 100.005 m, the distance to be increasing
by 0.005 m for each tape length
(B) An increase in temperature causes a tape to increase in length and themeasured distance is
too large
(C) The straight distance between end points of a suspended tape isreduced by an amount
called the sag correction
(D) A 100 m tape of crosssection 10 mm × 0.25 mm stretches about 10 mm under 5 kg pull
Answer: Option B

Question No. 20

Forthe construction of highway (orrailway)
(A) Longitudinalsections are required
(B) Crosssections are required
(C) Both longitudinal and crosssections are required
(D) None of these
Answer: Option C

IRRIGATION MCQ

IRRIGATION MCQ

Question No. 01

The consumptive use of water for a crop
(A) Is measured as the volume of water per unit area
(B) Is measured as depth of water on irrigated area
(C) May be supplied partly by precipitation and partly by irrigation
(D) All the above
 Answer: Option D

Question No. 02

Canals taken off from ice-fed perennial rivers, are known
(A) Permanent canals
(B) Ridge canals
(C) Perennial canals
(D) Inundation canals
 Answer: Option C

Question No. 03

In gravity canals, F.S.L. is
(A) Always at the ground level
(B) Always below the ground level
(C) Generally 4 to 5 metres above the ground level
(D) Only a few cm above the ground level
 Answer: Option D

Question No. 04

The field capacity of a soil is 25%, its permanent wilting point is 15% and specific dry unity weight
is 1.5. If the depth of root zone of a crop, is 80 cm, the storage capacity of the soil, is
(A) 8 cm
(B) 10 cm
(C) 12 cm
(D) 14 cm
Answer: Option C

Question No. 05

If water table is comparatively high, the irrigation canal becomes useless, due to
(A) Large amount of seepage
(B) Water logging of the cultivated areas
(C) Uncertain water demand
(D) All the above
 Answer: Option D

Question No. 06

If A is the area of the surface, density of water, then
(A) Total pressure on the surface is e
(B) Depth of the point at which total pressure acts is equal to its moment of inertia divided by
(C) Depth of the centre of pressure is 2/3H vertically below the surface
(D) All the above
Answer: Option D

Question No. 07

In a syphon aqueduct
(A) Drainage passes over the canal and F.S.L. of the canal is below the bottom of the drainage
trough
(B) Drainage passes over the canal and F.S.L. of the canal is above the bottom of the drainage
trough
(C) Canal passes over the drainage and H.F.L. of the drainage is above the bottom of the canal
trough
(D) Canal passes over the drainage and H.F.L. of the drainage is below the bottom of the canal
trough
 Answer: Option C

Question No. 08

If the height of the hydraulic gradient line above the floor of thickness t is h and the specific gravity of the material of the floor is G, the minimum thickness t of the floor downstream of the
crest-wall, is given by the equation
(A) t = (h + 1)/(G + t)
(B) t = (h - 1)/(G + t)
(C) t = (h - 1)/(G - t)
(D) t = (h + 1)/G
 Answer: Option C

Question No. 09

To hold hydraulic jumps, baffle walls are provided in
(A) Sarda type falls
(B) English type falls
(C) Montague type falls
(D) Vertical type falls
 Answer: Option B

Question No. 10

Pick up the correct sequence of the part of a canal system from the following
(A) Head work-distributary-branch canal-minor
(B) Head works-main canal-branch canal-distributary-minor
(C) Head works-main canal-branch canal-minor-distributary
(D) Heads works-branch canal-main canal distributary, minor
 Answer: Option B

Question No. 11

The field capacity of a soil depends upon
(A) Capillary tension in soil
(B) Porosity of soil
(C) Both (a) and (b)
(D) Neither (a) nor (b)
 Answer: Option C

Question No. 12

The water face of the guide banks, is protected by
(A) One men stone pitching
(B) Two man stone pitching
(C) Three man stone pitching
(D) Four man stone pitching
 Answer: Option A

Question No. 13

Pick up the correct statement from the following
(A) Escapes are essential safety valves in a canal system
(B) The escapes must lead the surplus water to natural drainages
(C) The escapes are aligned to take advantage of contours of lower values
(D) All the above
 Answer: Option D

Question No. 14

For a unique design of a channel by Kennedy's theory
(A) Its breadth must only be known
(B) Its depth must only be known
(C) Its breadth and depth ratio must only be known
(D) All the above
 Answer: Option C

Question No. 15

The structure constructed to allow drainage water to flow under pressure through an inverted
syphon below a canal, is called
(A) Syphon
(B) Super passage
(C) Super-aqueduct
(D) Syphon aqueduct
 Answer: Option D

Surveying and Levelling

Question No. 01

To avoid large centering error with very short legs, observations are generally made
(A) To chain pins
(B) By using opticalsystem for centering the theodolite
(C) To a target fixed on theodolite tripod on which theodolite may be fitted easily
(D) All the above
Answer: Option C

Question No. 02

Different grades are joined together by a
(A) Compoundcurve
(B) Transitioncurve
(C) Reversecurve
(D) Vertical curve
Answer: Option D

Question No. 03

Which of the following methods of theodolite traversing issuitable for locating the details which
are far away from transit stations?
(A) Measuring angle and distance from one transitstation
(B) Measuring anglesto the point from at least two stations
(C) Measuring angle at one station and distance fromother
(D) Measuring distance from two points on traverse line
Answer: Option B

Question No. 04

The line of collimation method of reduction of levels, does not provide a check on
(A) Intermediatesights
(B) Fore sights
(C) Back sights
(D) Reduced levels
Answer: Option A

Question No. 05

Which of the following methods of contouring is mostsuitable for a hilly terrain?
(A) Directmethod
(B) Squaremethod
(C) Cross-sectionsmethod
(D) Tachometricmethod
Answer: Option D

Question No. 06

The chord of a curve lessthan peg interval, is known as
(A) Small chord
(B) Sub-chord
(C) Normal chord
(D) Short chord
Answer: Option B

Question No. 07

The size of a plane table is
(A) 750 mm × 900 mm
(B) 600 mm × 750 mm
(C) 450 mm × 600 mm
(D) 300 mm × 450 mm
Answer: Option B

Question No. 08

If the reduced bearing of a line AB is N60°W and length is 100 m, then the latitude and departure
respectively of the line AB will be
(A) +50 m, +86.6 m
(B) +86.6 m, -50 m
(C) +50 m, -86.6 m
(D) +70.7 m, -50 m
Answer: Option B

Question No. 09

A lemniscate curve between the tangents will be transitional throughout if the polar deflection
angle of its apex, is
(A) ∆/2
(B) ∆/3
(C) ∆/4
(D) ∆/6
Answer: Option D

Question No. 10

Contour interval is
(A) Inversely proportional to the scale of the map
(B) Directly proportional to the flatness of ground
(C) Largerfor accurate works
(D) Larger if the time available is more
Answer: Option A