Design Of Steel Structures Set 12 MCQs

Q1 | If L is the overall length of a combined footing having A as its area, d being the distance betweenthe centre of gravity of the base and centre of the base, the larger width b is

(a/l) + (3ad/l²)

(a/l) + (6ad/l²)

(a/l) - (6ad/l²)

(a/l) - (3ad/l²)

Q2 | Select the correct statement

Material cost of a rivet is higher than that of abolt

Tensile strength of a bolt is lesser than that of a rivet

Bolts are used as a temporary fastening whereas rivets are used as permanentfastenings

Riveting is less noisy than bolting

Q3 | In a gusseted base, when the end of the column is machined for complete bearing on the base plate, then the axial load is assumed to be transferred to base plate

Fully by direct bearing

Fully through fastenings

50% by direct bearing and 50% through fastenings

75% by direct bearing and 25% through fastenings

Q4 | If the floor is supported at or near the bottom but top chords of a bridge is notbraced, then the bridge is called

Deck type

Through type

Half through type

Double deck type

Q5 | The elastic strain for steel is about

1/12 of strain at the initiation of strain hardening and about 1/120 of maximum strain

1/2 of strain at the initiation of strain hardening and about 1/12 of maximum strain

1/12 of strain at the initiation of strain hardening and 1/200 of maximumstrain

1/24 of strain at the initiation of strain hardening and about 1/200 of maximum strain

Q6 | In moment resistant connections, the moment resistance of riveted connectiondepends upon

Shear in rivets

Compression in rivets

Tension in rivets

Strength of rivets in bearing

Q7 | The moment of the couple set up in a section of a beam by the longitudinalcompressive and tensile force, is known as

Bending moment

Moment of resistance

Flexural stress moment

None of these

Q8 | The thickness of the web of a mild steel plate girder is less than d/200. If only one horizontal stiffener is used, it is placed at

The neutral axis of the section

2/3rd of the depth of the neutral axis from the compressionflange

2/5th of the depth of the neutral axis from the compressionflange

2/5th of the height of the neutral axis from tensionflange

Q9 | The most commonly used sections in lateral system to carry shear force in built upcolumns, are

Rolled steel flats

Rolled angles

Rolled channels

All the above

Q10 | The bracing between two columns of a steel tank will be designed to resist

Horizontal shear due to wind or earthquake only

Horizontal, shear due to wind or earthquake + 2.5% of column loads

Column loads + 2.5% of horizontal shear due to wind or earthquake

Column loads + full horizontal shear due to wind orearthquake

Q11 | A beam may be designed as a cased beam if

Section is of double open channel form with the webs not less than 40 mmapart

Overall depth and width of the steel section do not exceed 750 and 450 mmrespectively

Beam is solidly encased in concrete with 10 mm aggregate having 28 days strength 160kg/cm2

All the above

Q12 | In a built up beam actual bending compressive stress fbc is given by (when y1 isthe distance of the edge of the beam from the neutral axis).

fbc = (M/Ixx) × y

fbc = (Ixx/M) × y

fbc = (Ixx/M) + y

fbc = (M/Ixx) + y

Q13 | If the thickness of a structural member is small as compared to its length andwidth, it is classified as

One dimensional

Two dimensional

Three dimensional

None of these

Q14 | Compression members composed of two channels back-to-back and separated by a small distance are connected together by riveting so that the minimum slenderness ratio of each member between the connections, does not exceed

40

50

60

70

Q15 | The connection of intermediate vertical stiffeners to the web, not subjected to external loads, shall be designed for a minimum shear force (kN/m) of (Where, t = the web thickness in mm and h = the outstand of stiffener in mm)

75 t²/h

125 t3/h²

125 t²/h

175 t²/h

Q16 | When the upper column does not provide full bearing area over lower column, the column splice is provided with the following assumption

Bearing plate is assumed as a short beam to transmit the axial load to the lower column section

Axial load is assumed to be taken by flanges

Load transmitted from the flanges of upper column and reactions from the flanges of lower columns are equal and form a couple

All the above

Q17 | For the economical design of a combined footing to support two equal column loads, the projections of beams in lower tier are kept such that bending moment under column is equal to

Bending moment at the centre of the beam

Half the bending moment at the centre of the beam

Twice the bending moment at the centre of the beam

None of these

Q18 | The allowable shear stress in the web of mild steel beams decreases with (Where 'h is thickness)

Decrease in h/t ratio

Increase in h/t ratio

Decrease in thickness

Increase in height

Q19 | On eccentrically loaded columns, the equivalent axial load may be obtained by

Adding the axial load, eccentric load, the product of the bending moment due to eccentric load and the appropriate bending factor

Adding the axial load and eccentric load and subtracting the product of bending moment and appropriate bending factor

Dividing the sum of axial load and eccentric load by the product of the bending moment and appropriate bending factor

None of these

Q20 | In a truss girder of a bridge, a diagonal consists of mild steel flat 4001.S.F. and carries a pull of 80 tonnes. If the gross-diameter of the rivet is 26 mm, the number of rivets required in the splice, is

6

7

8

9

Q21 | When the bolts are subjected to reversal of stresses, the most suitable type of boltis

Black bolt

Ordinary unfinished bolt

Turned and fitted bolt

High strength bolt

Q22 | The size of a butt weld is specified by the effective throat thickness which in the case of incomplete penetration, is taken as

½ of the thickness of thicker part

¾ of the thickness of thicker part

¾ of the thickness of thinner part

7/8 of the thickness of thinner part

Q23 | In a built up section carrying a tensile force, the flanges of two channels are turnedoutward

To simplify the transverse connections

To minimise lacing

To have greater lateral rigidity

All the above

Q24 | The overlap of batten plates with the main members in welded connections should be more than

3 t

4 t

6 t

8 tt

Q25 | Modified moment of inertia of sections with a single web, is equal to moment of inertia of the section about Y-Y axis at the point of maximum bending moment and is multiplied by the ratio of

Area of compression flange at the minimum bending moment to the corresponding area at the point of maximum bending moment

Area of tension flange at the minimum bending moment of the corresponding area atthe point of maximum bending moment

Total area of flanges at the maximum bending moment to the corresponding area at the point of maximum bending moment

None of these