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
Correct Answer :
A. 10 m
Related Questions
The channels get twisted symmetrically with regard to its axis
Parallel to flanges
Parallel to web
Perpendicular to flanges
Perpendicular to web
If fbt and fc are the co-existent bending tensile stress and shear stress in a member, the equivalent stress fc is
√(fbt² + fc²)
√(fbt² + ½fc²)
√(fbt² + 3fc²)
√(fbt² - 3fc²)
The minimum width B of a solid casing for a cased beam, is equal to
B = b + 25 mm
B = b + 50 mm
B = b + 75 mm
B = b + 100 mm
Select the correct statement
Material cost of a rivet is higher than that of a bolt
Tensile strength of a bolt is lesser than that of a rivet
Bolts are used as a temporary fastening whereas rivets are used as permanent fastenings
Riveting is less noisy than bolting
The main advantage of a steel member, is:
Its high strength
Its gas and water tightness
Its long service life
All the above
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 or earthquake
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
Pitch of tacking rivets, when double angles connected back to back and acting as tension members should not be more than
500 mm
600 mm
1000 mm
300 mm
The portal bracing in a truss bridge is used to
Transfer load from top of end posts to bearings
Keep the rectangular shape of the bridge cross-section
Stiffen the structure laterally
Prevent the sides-way buckling of top chord
The strength of ISA 125 = 75 × 10 mm used as a tie member with its longer leg connected at the ends by 27 mm diameter rivets, is
26,000 kg
26,025 kg
26,050 kg
26,075 kg
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
Rivets connecting flange angles to cover plates in a plate girder are subjected to
Horizontal shear only
Vertical load only
Both (A) and (B)
None of the above
In rolled steel beams, shear force is mostly resisted by
Web only
Flanges only
Web and flanges together
None of these
Design of a riveted joint, is based on the assumption:
Load is uniformly distributed among all the rivets
Shear stress on a rivet is uniformly distributed over its gross area
Bearing stress in the rivet is neglected
All the above
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
The most commonly used sections in lateral system to carry shear force in built up columns, are
Rolled steel flats
Rolled angles
Rolled channels
All the above
The effective length of a battened column is increased by
5 %
10 %
15 %
20 %
Load factor is
Always equal to factor of safety
Always less than factor of safety
Always greater than factor of safety
Sometimes greater than factor of safety
Allowable working stress corresponding to the slenderness ratio of double angles placed back to back and connected to one side of a gusset plate, is reduced to
50 %
60 %
70 %
80 %
When the bolts are subjected to reversal of stresses, the most suitable type of bolt is
Black bolt
Ordinary unfinished bolt
Turned and fitted bolt
High strength bolt
The allowable stress in axial tension for rolled I-sections and channels, is taken as
1420 kg/cm2
1500 kg/cm2
2125 kg/cm2
1810 kg/cm2
The range of economical spacing of trusses varies from
L/3 to L/5
L/4 to 2L/5
L/3 to L/2
2L/5 to 3L/5, where L is span
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
An axial loaded column is supported on a slab base whose projection is 8 cm. If the intensity of pressure from concrete is 40 kg/cm2 and allowable bending stress in slab base is 1890 kg/cm2, the thickness (t) of the slab base, is
t = √(21/64)
t = √(64/21)
t = 21/64
t = 64/21
In the cross-section of a weld, throat is the
Minimum dimension
Average dimension
Maximum dimension
None of the above
Tacking rivets in compression plates not exposed to the weather, have a pitch not exceeding 300 mm or
16 times the thickness of outside plate
24 times the thickness of outside plate
32 times the thickness of outside plate
36 times the thickness of outside plate
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
Generally the purlins are placed at the panel points so as to avoid
Axial force in rafter
Shear force in rafter
Deflection of rafter
Bending moment in rafter
The centrifugal force due to curvature of track is assumed to act on the bridge at a height of
1.23 m above the rail level
1.50 m above the rail level
1.83 m above the rail level
2.13 m above the rail level
According to IS Specifications, the effective length of a column effectively held in position at both ends and restrained in direction at one end is taken as
0.67 L
0.8 L
L
1.5 L