For steel members not exposed to weather, the thickness of steel should not be less than
4.5 mm
6 mm
8 mm
10 mm
Correct Answer :
B. 6 mm
Related Questions
Effective length of a column effectively held in position and restrained in direction at one end but neither held in position nor restrained in direction at the other end, is
1.5 L
0.67 L
0.85 L
2 L
Study the following statements. (i) Top lateral bracing prevents the sides-way buckling of the chord. (ii) Sway bracing keeps the rectangular shape of the bridge crosssection. (iii) Sway bracing transfers the load from top of end posts to bearings. The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
All (i), (ii) and (iii)
A riveted joint may experience
Shear failure
Shear failure of plates
Bearing failure
All the above
The minimum pitch of rivet holes of diameter d should not be less than
d
1.25 d
1.5 d
2.5 d
Steel tanks are mainly designed for
Weight of tank
Wind pressure
Water pressure
Earthquake forces
The basic wind speed is specified at a height 'h' above mean ground level in an open terrain. The value of 'h' is
10 m
20 m
25 m
50 m
If the moment of inertia of a section about its axis is I and its effective sectional area is A, its radius of gyration r about the axis, is
r = I/A
r = √(I/A)
r = (I/A)
r = √(A/I)
Pick up the correct statement from the following:
The minimum pitch should not be less than 2.5 times the gross diameter of the river
The minimum pitch should not be less than 12 times the gross diameter of the rivet
The maximum pitch should not exceed 10 times the thickness or 150 mm whichever is less in compression
All the above
When the ratio of the moment M to axial load P is greater than L/6, the resultant of the compressive bearing pressure which acts at a distance Y from one side, is given by
y = (L/3) - (M/P)
y = (L/2) - (P/M)
y = (L/2) + (M/P)
y = (L/3) + (M/P)
In a built up beam actual bending compressive stress fbc is given by (when y1 is the distance of the edge of the beam from the neutral axis).
fbc = (M/Ixx) × y₁
fbc = (Ixx/M) × y₁
fbc = (Ixx/M) + y₁
fbc = (M/Ixx) + y₁
Pick up the correct statement from the following:
Tacking rivets are used if the minimum distance between centres of two adjacent rivets exceeds 12 t or 200 mm, whichever is less
Tacking rivets are not considered to calculate stress
Tacking rivets are provided throughout the length of a compression member composed of two components back to back
All the above
A structural member subjected to tensile force in a direction parallel to its longitudinal axis, is generally known as
A tie
A tie member
A tension member
All the above
The permissible bearing stress in steel, is
1500 kg/cm2
1890 kg/cm2
2025 kg/cm2
2340 kg/cm2
Column footing is provided
To spread the column load over a larger area
To ensure that intensity of bearing pressure between the column footing and soil does not exceed permissible bearing capacity of the soil
To distribute the column load over soil through the column footing
All the above
The bending moment for filler joists at the middle of an intermediate span, is
WL²/10
- WL²/10
- WL²/12
WL²/12
The live load for a sloping roof with slope 15°, where access is not provided to roof, is taken as
0.65 kN/m²
0.75 kN/m²
1.35 kN/m²
1.50 kN/m²
When a load is transferred through one surface to another surface in contact, the stress is known as
Tensile stress
Compressive stress
Shearing stress
None of these
Diameter of a rivet hole is made larger than the diameter of the rivet by
1.0 mm for rivet diameter upto 12 mm
1.5 mm for rivet diameter exceeding 25 mm
2.0 mm for rivet diameter over 25 mm
None of these
The moment-curvature relation at a plastic hinge is
Linear
Parabolic
Constant moment for all curvatures
Constant curvature for all moments
In a built up section carrying a tensile force, the flanges of two channels are turned outward
To simplify the transverse connections
To minimise lacing
To have greater lateral rigidity
All the above
The main assumption of the method of simple design of steel frame work, is:
Beams are simply supported
All connections of beams, girders and trusses are virtually flexible
Members in compression are subjected to forces applied at appropriate eccentricities
All the above
If f is the maximum allowable bending stress in a tension member whose radius of gyration is r and depth is 2y, the required cross sectional area A is given by
A = My/fr²
A = My²/fr²
A = My/fr
A = My/f²r²
Water pressure in a 80 cm water main is 10 kg/cm2. The minimum thickness of the metal required for the water main, not to be stressed more than 200 kg/cm2, is
1 cm
1.5 cm
2 cm
2.5 cm
Perforated cover plates are particularly suitable for built up sections consisting of
Channels placed back to back
Channels placed toe to toe
Four angle box section
All the above
Slenderness ratio of a compression member is
Moment of inertia/Radius of gyration
Effective length/Area of cross-section
Radius of gyration/Effective length
Radius of gyration/ Area of cross-section
For a cantilever beam of length L continuous at the support and unrestrained against torsion at the support and free at the end, the effective length l is equal to
l = L
l = 2L
l = 0.5L
l = 3L
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
A 20 mm dia steel bar which is subjected to an axial tension of 2300 kg/cm2 produces a strain of 0.004 cm. If Young's modulus of steel is 2.1 × kg/cm2, the bar is
In the elastic range
In the plastic range
At yield point
None of these
An imaginary line along which rivets are placed, is known as
Rivet line
Back line
Gauge line
All the above
The number of seismic zones in which the country has been divided is
3
5
6
7