technical quiz 6 levels

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Level 11111

1. A rectangular beam of length I supported at its two ends carries a central

concentrated load W at its centre. The maximum deflection occurs

at the ends

at 1/3 from both ends

at the mid span

at 1/4 from both ends

Click here for answer

2. If the depth is kept constant for beam of uniform strength then its width

will vary proportional to

M

Sqrt(M)

M^2

M^3


3. When a beam deflects into a uniform strength then its width will vary

proportional to

I/2R

I/8R

I^2 /8R

I^2 /2d




4. The longitudinal stress in a thin cylindrical shell is

Pd/4t

Pd/2t

Pt/4d

Pt/2d


5. The ratio of maximum shear stress and average shear stress for a

rectangular section is

1.5

2

2.5

3


6. A fixed beam of span L carries a central point load W. The maximum

sagging bending moment in the beam is

WL/2

WL/4

WL/8

WL/16


7. Air entrainment in the concrete increases

workability



strength

the effects of temperature

the unit weight


8. The relation between modulus of rupture Fcr and characteristic strength of

concrete Fck is given by

Fcr = 0.35 S Fck

Fcr = 0.5 S Fck

Fcr = 0.7 S Fck

Fcr = 1.2 S Fck


9. The compressive strength of 100 mm cube as compared to 150 mm cube is

always

less

more

equal

may be any of the above


10. For a slab supported on its four edges with corners held down and loadeduniformly, the Marcus correction factor to the moments obtained by Grashoff

Rankine's theory

is always less than 1

is always greater than 1



can be more than 1

can be less than 1


11. For bars in tension a standard hook has an anchorage value equivalent to

a strength length of

8

12

16

24


12. Cube strength of controlled concrete to be used for pre-tensioned and

post-tensioned work respectively should not be less than

350 Kg/cm^2 and 420 Kg/cm^2





13. The creep strains are

caused due to dead loads only

caused due to live loads only

caused due to both dead and live load



independent of loads


14. Ratio of compressive strength to tensile strength of concrete

increases with age

decreases with age

remains constant

none of the above


15. In limit state design of concrete for flexure, the area of stress block is

taken as

0.36 Fck Xu

0.42 Fck Xu

0.446 Fck Xu

0.53 Fck Xu


16. The fitness modulus of the fine aggregate is in the range of

2.0 to 3.5

3.5 to 5.0

5.0 to 7.0

6.0 to 8.5




17. According to IS:456-1978, the maximum reinforcement in a column is

2%

4%

6%

8%


18. The minimum cover in a slab should neither be less than the diameter of

bar nor less than

10 mm

15 mm

20 mm

13 mm


19. If the permissible stress in steel in tension is 140 N/mm^2, Permissible

stress in concrete in bending compression is 5N / mm^2. Then the depth of

neutral axis for a singly reinforced rectangular balanced section will be

0.35 d

0.40 d

0.45 d

dependent on grade of concrete also


20. The slab is designed as one way if the ratio of long span to short span

is



less than 1

between 1 and 1.5

between 1.5 and 1.2

greater than 2


21. In any beam when the moment of inertia about the neutral axis is

doubled, its deflection is

doubled

tripled

halved

minimum


22. The limits of percentage of the longitudinal reinforcement in a column is

given by

0.15% to 2%

0.8% to 4%

0.8% to 6%

0.8% to 8%


23. A rigid prop provided for a beam

brings the bending for a beam



brings the deflection at the prop to zero

brings the slopes at the section to zero

brings the shear force at the section to zero


24. In a simply supported beam AB with a concentrated load W at a distance

'a' from support A and 'b' from support B, the deflection under the load is

wa^2 b^2 / 3EIL

wa^2 / 3EI

wa^2 b^2 /3EI

wa^2 b + 2/EIL


25. For the design of retaining walls the minimum factor of safety against

over-turning is taken as

1.5

2.0

2.5

3.0


26. A cantilever beam is loaded by a point load at the free end. It is likely to

fail by B.M.

under the load

at mid span



at support

none


27. The distance between centre lines of a broad gauge is 1.686m. The most

economic length of sleeper for efficient distribution of B.M. is

1.866 m

2.866 m

3.866 m

0.866 m


28. In a simply supported beam of span L carrying an eccentric couple M

acting at a distance A from the left support, the reaction included at the

support is

M/L

L/M

ML

1/ML


29. Area of shear force diagram between two sections is

70 KNm

140 KNm

280 KNm



can not be found


30. The section modulus of square section of side A is

a^2 /6

a^3 /6

a^4 /12

a^3 /12


31. The minimum percentage of mild steel reinforcement in walls of RCC

water tanks of 450 mm thick is about

0.20

0.30

0.24

0.16


Level 2222

1. A beam of span L m is simply supported at the ends. It is loaded by two

equal clockwise moments at the supports. Point of contra flexure acts at



0.25 m from left support

0.25 m from right support

At mid span

none of these


2. The ratio of flexibility of loose beams (b x d) places one over the other to

the flexibility of one integral beam (nb x d) is

h^2

1/h^2

1

h^3


3. The earth pressure at a depth d is P the earth pressure at depth d/2 is

P

4P

0.5P

0.25P


4. A reinforced concrete column is considered as a short column, if its

slenderness ratio L/bn is less than

20



18

15

12


5. A common footing provided for two columns is called a

mat foundation

raft foundation

combined footing

common foundation


6. For reinforced concrete (M15) members immersed in sea water the cover

shall be

Same as in the usual case

25 mm more than the cover in the usual cases




7. The modulus of elasticity of steel is

150 KN/mm^2

200 KN/mm^2

250 KN/mm^2



275 KN/mm^2


8. The number of rivets for connecting a strut to a gusset plate shall not be

less than

2

3

4

5


9. The inclination of a lacing bar with the axis of the compression member

shall not exceed

60

70

45

30


10. For unstiffened webs of girders, the thickness of web shall not be less

than

D1/50

D1/85

D1/100

D1/150




11. Spacing of vertical stiffeners in a girder shall not be less than

0.50d

0.40d

0.33d

0.25d


12. The maximum bending moment for a purling may be taken as

WL/10

WL/8

WL/12

WL/15


13. If the foundations of all the columns of a structure are designed on the

total live and dead load basis, then

there will be no settlement of columns

there will be no differential settlements

the settlement of exterior columns will be more than interior columns

the settlement of interior columns will be more than exterior columns


14. To minimize the effect of differential settlement, the area of footing

should be designed for



dead load only

dead load + live load

dead load + fraction of live load

live load + fraction of dead load


15. A reduction factor Cr, load carrying capacity of a long columns is given

by

Cr = 1.25 - Le/24b

Cr = 1 - Le/48b

Cr = 1.25 - Le/48b

Cr = 1.5 - Le/48b


16. Normally pre-stressing wires are arranged in the

upper part of the beam

lower part of the beam

centre

anywhere


17. The shear stress intensity changes from the centre to the surface of the

shaft with

uniform rate



varying rate

remains same

all the above


18. The formula T/J = NO/L = fs/r when applied to torsion of closely coiled

helical spring, the value of J will be calculated with

mean diameter of the coil D

the diameter of wire of spring

mean of D and d

(2D + d)3


19. The shear stress intensity is minimum at

axis of shaft

surface of the shaft

any inside layer of shaft

all the above


20. A steel member which is subjected to primary tension is called

Tie

Tie or beam

Strut



Sling


21. Sliding failure occurs in a solid gravity dam when

Resultant of all forces cuts the base of the dam outside

Resultant of all force cuts the base of the inner middle third point

Ratio of overturning moments exceeds one

Shear friction factor is less than 1.5


22. Mean velocity of flow in a river can be directly measured by means of

Boats

Dams

Surface floats

Rod floats


23. The formula used to calculate maximum flood discharge for deccan

catchments is

Dicken's formula

Ryve's formula

Ali Nawab Jung Bahadur formula

Ingli's formula




24. Direct run off is the sum of

Surface run off and mass flow

Base flow and ground water run off

Deployed sub surface run off and deep percolation

Surface run off and interflow


25. A fluid is a substance that

always expands until it fills any container

is parctically incompressible

cannot remain at rest under the action of a shear force

cannot be subjected to shear forces


26. In Sutro weir the discharge is proportional to

H

H^1/2

H^3/2

H^5/2


27. Which of the following has highest coefficient of discharge

Sharp edged orifice



Venturimeter

Borda's mouth piece running free

Cippoletti weir


28. ML^-1 T-2 is the dimension of

Force

Pressure

Energy

Power


29. Cavitation is caused by

high velocity

low barometric pressure

low pressure

high pressure


30. Number of rivets required in a joint is

load/shear strength of a rivet

load/bearing strength of a rivet

load/tearing strength of a rivet



load/rivet value


31. The point of contraflexure occurs in

cantilever beams only

continuous beams only

over hanging beams only

all types of beams


Level-----3



1. According to Unwin's formula, if t is thickness of the plate in mm, the

nominal diameter of the rivet is

d = 1.91 t

d = 1.91 t^2

d = 1.91 St

d = 1.91 St^3


2. The slenderness ratio of a column is zero when its length

is zero

is equal to its radius of gyration

is supported on all sides throughout its length

is between the points of zero moments


3. According to IS; 800-lacing bars resists transverse shear equal to

1.0% of the axial load





4. When the length of tension member is too long

a wire is used



a rod is used

a bar is used

a single angle is used


5. A major beam on a building structure, is known as

a girder

a floor beam

a main beam

all the above


6. For simply supported beams, the maximum permitted deflection is

1/325 of the span

1/350 of the span

1/375 of the span

1/400 of the span


7. In case of cantilever beams the ratio of span to the depth should not

exceed

4

8

12



16


8. In a fillet weld placed on the sides of the base, the metal experiences

shear

tension

compression

all the above


9. Steel is efficiently used in

under reinforced section

over reinforced section

under and over reinforced section

none of the above


10. The maximum area of tension reinforcement in a beam is

4% of bD

4.5% of bD

5% of bD

5.5% of bD


11. The large moment of resistance of T-beam section is due to



width of rib

amount of steel

composite action between the flanges and the rib

depth of rib


12. If in any given pane, one end of a column is unrestrained, its unsupported

length l, shall not exceed

100 b^2 /D

120 b^2 /D

125 b^2 /D

140 b^2 /D


13. The diameter of lateral ties in a column shall not be less than

6 mm

5 mm

8 mm

10 mm


14. The bending moment at a section of a beam is given by wx^3/6 then the

expression for the rate of loading is

wx^4 /24



wx^2 /2

wx

w


15. The torque produced in a circular shaft rotating at 100 r.p.m. to produce 1

h.p. is _____ Kgcm

716.2

816.2

916.2

616.2


16. The weight of foundation may be assumed to be

15% of the column loads





17. In a continuous footing the area of longitudinal reinforcement required in

the direction of wall is

0.3%

0.2%



0.5%

0.4%


18. The net upward pressure on footing p is given by

W + W1/W.q.

W.q./W + W1

W - W1/W.q.

W.q./W - W1


19. Partial safety factor m for steel in limit state design is

0.5

1.0

1.5

1.15


20. The design strength of materials Fs is given by

1.1 f/Rm

f/Rm

f

0.9f




21. The pre-stressed concrete induces artificially _____ stress in a structure

before it is loaded

compressive

tensile

shear

bending


22. According to IS code the total amount of shrinkage for a post tensioned

member is taken as

2 x 10^4 / log10 (T+2)

3 x 10^-4 / log10 (T+3)

3 x 10^-3 / log10 (T+3)

2 x 10^-3 / log10 (T+3)


23. The state at which tendon force is released permanently on the concrete

is called

Transfer

Anchoring

Pre-tensioning

Post-tensioning




24. In a thin cylindrical shell if F1 is the hoop stress and F2 is the longitudinal

stress induced, maximum shear stress at any point of the material is given

by

F1 + F2 / 2

F1 - F2 / 2

F1F2 / 2

2F1 / F2


25. A beam is fixed at one end and is supported at the other end to the level

of the fixed end by means of a rigid prop. At the propped end, for any appliedload

only flexural moment is zero

the flexural moment as well as deflection is zero

the slope as well as the deflection is zero

the slope as well as the flexural moment is zero


26. The thickness of lacing bar used in steel ties should not be less than

6 mm

4.5 mm

B/40

L/40


27. Mohr's theorem I gives _____ between two tangents on the elastic line of

beams



Slope

Deflection

S.F.

B.M.


28. IS code of practice for steel is

456

800

546

none


29. Select cash/commercial crop from the following

Maize

Paddy

Cotton

Wheat


30. Canal lining

Increases water logging area

Decreases water logging area



Does not affect water logging area

Maintains constant water logging area


31. The diameter of transverse reinforcement of columns should be equal to

1/4 of the diameter of the main steel rods but not less than

4 mm

5 mm

6 mm

7 mm


Level 4444444

1. The world famous constant radius arch dam Hoover is in

Italy



Russia

U.S.A

U.K.


2. Presently percentage of area irrigated to that of total cultivated area is

80%

33%

27%

40%


3. Duty of well water is more than canal water because

Conveyance losses in well irrigation are less

Well water is clear than canal water

Lifting of water increases cost of well water

Well water is used economically


4. Weirs constructed on permeable foundation are likely to fail due to

Piping

Crushing

Sliding



All the above


5. Inlet and outlet are provided as cross drainage measure when the

discharge of the drain is

very high

high

medium

low


6. The unit of hydraulic mean radius is

m^3

radians

m^2

m


7. A water shed canal

irrigates only on one side

avoids the cross drainage works

is generally aligned parallel to the contours of the area

is most suitable in hilly areas




8. The meander pattern of a river is developed by

average discharge

dominant discharge

maximum discharge

critical discharge


9. A unit hydrograph has one unit of

rainfall duration

rainfall excess

time base of direct runoff

discharge


10. For a flood control reservoir, the effective storage is equal to

useful storage - valley storage

useful storage + surcharge storage

useful storage - surcharge storage

useful storage + surcharge storage - valley storage


11. When the reservoir is full, the maximum compressive force in a gravity

dam is produced

at the toe



at the heel

within the middle third of base

at centre of base


12. When the fluid properties do not change with time, it is a _____ flow

steady

uniform

unsteady

non-uniform


13. The coefficient of discharge for a convergent divergent mouth piece is

2/3

1/3

1/2

3/4


14. A horizontal pipe of carrying liquid increases its diameter d1 to d2. The

pressure increase is maximum when d1 to d2 is

1/2

1/3

1/Sqrt(2)



1/4


15. Diameter of nozzle d for maximum power transmission is given as

d = (D^5 / 8fl)^1/4

d = (D^5 / 8fl)^1/5

d = (D^4 / 8fl)^1/5

d = (8fl/5)^1/4


16. In a triangular notch an error of 1% in measuring head will produce

_____ error in discharge

1%

1.5%

2%

2.5%


17. Aeration holes are provided

in a weit with end contraction

in a suppresses weir

in a cippoletti weir

in all weirs




18. The head of water supplied to a nozzle is 12 m. The loss of head due to

friction at at maximum power transmission is

3 m

4 m

1.2 m

6 m


19. Weep holes are provided in canal lining to

improve strength of lining

give additional anchorage against sliding

provide water into branch canals

have drainage facility


20. The flow in a river during floods may be classified as

laminar flow

streamline flow

irrotational flow

turbulent flow


21. The first step in the operation of a centrifugal pump is

pumping



straining

priming

none of these


22. Developement of _____ in river meandering causes violent changes in

river

delta

critical velocity

cut off

turbulance


23. An impermeable foundation which neither contains water nor transmits

any water is called

Aqueduct

Aquifer

Aquiclude

Confined aquifer


24. The maximum quantity of water that can be guaranteed during a critical

dry period is known as _____ yield

critical

dry



safe

all the above


25. Rabi crops pertains to

throughtout the year

summer season

monsoon season

winter season


26. The velocity measured at a depth of _____ gives the mean velocity using

the current meter

0.6 m

0.5 m

0.6 depth

0.5 depth


27. When thickness of imprevious core in an earthen dam is less than _____

or less than the height of the dam, then the dam is known as diaphram type,

otherwise it would be zoned earth dam

3 m

5 m

10 m



15 m


28. Generally useful life of a reservoir is considered terminated when its

effective storages is reduced by _____ of the design capacity of thereservoir

100%

80%

50%

20%


29. When the nappe of a spillway confirms to the profile of lower nappe

water, falling from a sharp rested weir, when it is called as

straight drop spillway

chute spillway

siphon spillway

ogee spillway


30. The last length of the river before it falls into the sea is known as

mountainous stage

trough-stage

delta stage

sub-mountainous stage




31. For a number of columns constructed in a row, the type of foundation

provided is

footing

raft

strap

strip


Level 5555

1. The centre of pressure of a plane submerged area is

always below the centre of gravity of the are

coincident with centroid of area if its plane is vertical

always above the centroid of are

independent of the inclination of area


2. The forces coming over the dam is mainly resisted by

water pressure

uplift pressure

self weight of the dam



all the above


3. The turbine in which the runner blades move and adjust themselves during

the operation of turbine is called _____ turbine

Francis

Kaplan

Modern Francis

All the above


4. A centrifugal pump converts _____ energy into hydraulic energy

electrical

mechanical

kinetic

pressure


5. Falling drops of rain acquire spherical shape on account of

viscosity

surface tension

vapour pressure

compressibility




6. The vertical component of pressure force on a submerged curved surface is

equal to

Its horizontal component

the force on a horizontal projection of the curved surface

the weight of liquid vertically above the curved surface

the product of pressure at centroid and surface area


7. Coefficient of resistance Cr for an orifice is equal to

(1 - Cv^2)

(1/Cv^2 - 1)

(1 / Cc^2 Cd^2)

(1 - Cd^2 Cv^2)


8. A hydraulic jump is used for

increasing the depth of flow

reducing the energy of flow

decreasing the velocity of flow

reducing turbulence


9. For laminar flow through a pipe, the energy correction factor is

1.03



1.05

1.33

2.00


10. The force required to act upon the jet of water to change the velocity

either in direction or in magnitude is called by

hydrostatic force

dynamic force

absolute force

power canal


11. The canal through which water is led into mouth of the penstocks is

fore day

tail race

trash rack

power canal


12. The device fitted to a reciprocating pump for smooth and uniform flow is

called

accelerator

impeller



booster

air vessel


13. Surge tank is provided to prevent the effect of

racing of turbine

pressure reaction

water hammer

spilling of water


14. The minimum distance between centres of rivet holes should be

2.5 times the hole diameter

1.5 times the hole diameter

3 times of hole diameter

equal to the hole diameter


15. In turbine governing system, the pump used is

centrifugal pump

reciprocating pump

gear pump

uplift pump




16. Bombay harbour is an example of _____ harbour

artificial

natural

excavating

dreading


17. The operation of removal of external material from the sea or river bed is

known as

digging

shoveling

excavating

dredging


18. In case of an external mouth piece the pressures at vena contracta is

equal to

Ha - 0.98 H

Ha - 0.89 H

Ha - 0.77 H

Ha - 0.87 H




19. If the Young's modulus of elasticity of a material is twice its modulus of

rigidity, then the poisson's ratio of the material is

-1

-0.5

0.5

0


20. For an isotropic, homogeneous and elastic material obeying Hook's law,

number of independent elastic constants is

2

3

4

1


21. If a material has identical properties in all directions, it is said to be

homogeneous

isotropic

elastic

orthotropic


22. According to Unwin's formula, the diameter of rivet in mm to suit the t

mm thickness of plate is given by



6t

6 Sqrt(t)

1.9 Sqrt(t)

1.5t + 4


23. The sum of normal stresses is

constant

variable

dependent on the planes

none of the above


24. A simply supported beam of length l carries a load varying uniformly from

zero at left end to maximum at right end. The maximum bending moment

occurs at a distance of

1/Sqrt(3) from left end

1/3 from left end

1/Sqrt(3) from right end

1/3 from right end


25. Of the two prismatic beams of same material, length and flexural

strength, one is circular and other is square in cross-section, the ratio of

weights of circular and square beam is

1.118



1.342

1.000

0.793


26. For no torsion, the plane of bending should

be parallel to one of the principal axis

pass through shear centre of section

pass through neutral axis of the section

pass through centre of gravity of the section


27. A beam of uniform strength has at every cross-section same

bending moment

bending stress

deflection

stiffness


28. Effective length of a column fixed at one end hinged at the other end is

1/2

1/Sqrt(2)

2



Sqrt(2)


29. Soundness of cement is tested by

permeability

impact

Le chaterlier

Los angles


30. During setting and hardening of concrete _____ is generated

Energy

Heat

Temperature

Radiation


31. In a pre-stressed member it is advisable to use

low strength concrete only

high strength concrete only

low strength concrete but high tensile steel

high strength concrete and high tensile steel




Level 66666

1. The depth of critical N.A. of the beam is

(m.d) / r

(m + r) / d

(m x d) / (m + r)

none of these


2. Minimum spacing between horizontal parallel reinforcement of the same

size should not be less than _____ diameters

4

3

2

1


3. The maximum span to depth ratio of a simply supported slab spanning in

both direction is _____

25

30



35

50


4. The purpose of ribbed slab is to provide

Thermal insulation

Acoustic insulation

A plain ceiling

All of the above


5. In rectangular water tanks, maximum B.M. occurs when depth of water in

the tank is equal to _____ the length of short wall

1/4

1/2

3/4

1/5


6. Rapid hardening cement is actually early _____ cement

setting

strength

hardening

curing




7. The relation between tread I and rise R in cms is given by

4 + 2t = 30

2t + r = 30

2r + t = 60

2r + t = 30


8. Ductility of steel decreases with a percentage _____ of carbon steel

decrease

increase

improvement

reduction


9. _____ ratio of steel, within elastic limit, varies from 0.25 to 0.33

Compression

Extension

Impact

Poisson's


10. If unsupported length of a stanchion is 5 m, slenderness ratio is 100, the

least radius of gyration of the cross-section is _____ cm



50

60

10

5


11. The process of adding extra carbon to the surface of steel is known as

_____

Heat treatement

Carbon coating

Carburising

Carbon treatement


12. Hardening of metal is due to heating to a particular temperature and

followed by rapid cooling in a _____ media

Cooling

Tempering

Quenching

Freezing


13. Maximum shear force occurs at the edge of a base plate in a _____

footing

Stepped



Rectangular

Square

Grillage


14. The slenderness ratio of a tension member should not exceed 350, if the

member is subjected to _____ stresses resulting from wind force

Compressive

Tensile

Bending

Reversible


15. 0.67 is the effective length of a compression member _____

Fixed at both ends

Free at both ends

Held in position and restrain in direction at both ends

Fixed at both lower end and free at upper end


16. L/2 is the effective length of a column, fixed in _____ at its top and

bottom

position

direction



position & direction

none of these


17. 27t is the strength of ISA 155 x 75 x 10 used as a tie member with the

longer leg connected at the ends by a _____ mm dia rivet

22

25

27

32


18. The maximum deflection allowed in steel ties is

L/750

L/480

L/350

unlimited


19. The angle of inclination of lacing bars in steel ties should be more than

25

40

60

75




20. For normal loading conditions on a simply supported beam the breadth of

the beam can be assumed as nearly

1/12 of span of the beam





21. When a beam section spans over several supports continuously then the

beam at supports should be designed as

Singly reinforced beam

Doubly reinforced beam

Pre-stressed beam

Pre-cast beam


22. In a continuous slab the B.M. at middle of interior spans due to super

imposed load of intensity W Kg/m run will be

Wl^2 / 12

Wl^2 / 10

Wl^2 / 24

Wl^2 / 9




23. As per IS : 456 in a two-way slab, the width of the middle strip along

each span should be

3/8 of the width of span in that direction

3/8 of the width of span at right angles

3/4 of the shortest side of the slab

3/4 of width of the span in that direction


24. The reinforcement provided in the form of ties or stirrups or binders in a

column is known as

longitudinal reinforcement

transverse reinforcement

temperature reinforcement

distributary reinforcement


25. Load carrying capacity of long columns are less as compared to short

columns due to

buckling effect of columns

crippling effects of columns

bending effects of columns

twisting effect of columns


26. As per IS : 456 the thickness of footing edge on soils should not be less

than



10 cm

12 cm

15 cm

20 cm


27. Generally for piles the concrete used is of the grade

M100

M150

M200

M300


28. The shear force on a beam and the displacement are related by

V = El. d^2 y / dx^2

V = El. d^3 y / dx^3

V = El. d^4 y / dx^4

no relation at all


29. The shear stress in a beam is zero

At the centroid of the section

On the extreme free surface fibers



At the neutral axis but not at the centroid

At the free edges


30. The minimum strength of concrete that can be used in the foundations of

RCC water tanks of 450 mm thick is about

M15

M20

M25

M10


31. The carbon content in steel does not exceed

0.5%

1.0%

1.5%

2.0%


technical quiz 6 levels

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