The maximum slenderness ratio of a compression member carrying both dead and superimposed load is
180
200
250
350
Correct Answer :
A. 180
Related Questions
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:
Dead load includes self-weight of the structure and super-imposed loads permanently attached to the structure
Dead loads change their positions and vary in magnitude
Dead loads are known in the beginning of the design
None of these
A riveted joint may experience
Shear failure
Shear failure of plates
Bearing failure
All the above
The area Ap of cover plates in one flange of a built up beam, is given by
Ap = Zreqr + Zbeam/h
Ap = Zreqr + Zbeam/A
Ap = Zreqr × Zbeam/h
Ap = Zreqr - Zbeam/h
Tongue plates are provided in a steel girder at
The upper flange
The lower flange
The upper end of the web
The upper and lower ends of the web
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)
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
The safe working pressure for a spherical vessel 1.5 m diameter and having 1.5 cm thick wall not to exceed tensile stress 50kg/cm2, is
16 kg/cm2
18 kg/cm2
20 kg/cm2
22 kg/cm2
On steel structures the dead load is the weight of
Steel work
Material fastened to steel work
Material supported permanently
All the above
The effective length of a fillet weld should not be less than
Two times the weld size
Four times the weld size
Six times the weld size
Weld size
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
The stress in the wall of a thin cylinder subjected to internal pressure, is
Hoop compression
Shear
Torsional shear
Hoop tension
Economical depth of a plate girder corresponds to
Minimum weight
Minimum depth
Maximum weight
Minimum thickness of web
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
For a steel member of slenderness ratio 350, the allowable stress is 76 kg/cm2 if it is
HTW grade of thickness exceeding 32 mm
HT grade of thickness exceeding 45 mm
HT grade of thickness not exceeding 45 mm
All the above
Bolts are most suitable to carry
Shear
Bending
Axial tension
Shear and bending
As per ISI, rolled steel beam sections are classified into
Two series
Three series
Four series
Five series
Bearing stiffeners are provided at (i) The supports (ii) The mid span (iii) The point of application of concentrated loads The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
(i), (ii) and (iii)
The ratio of hydrostatic stress to the volumetric strain within the elastic range, is called
Modulus of elasticity
Shear modulus of elasticity
Bulk modulus of elasticity
All the above
The economical depth d of a web plate in which allowable bearing stress is fb, and the maximum bending moment is M, as suggested by Rawater and Clark, is
d = (M/fb)
d = 1.5 (M/fb)
d = 2.5 (M/fb)
d = 4.5 (M/fb)
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 at the 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
Pick up the incorrect statement from the following:
The nominal diameter of a rivet is its diameter before driving
The gross diameter of a rivet is the diameter of rivet hole
The gross area of a rivet is the cross-sectional area of the rivet hole
The diameter of a rivet hole is equal to the nominal diameter of the rivet plus 1.5 mm
Compression force in two end posts, the pin of a rocker bearing in a bridge is designed for
Bearing and shear
Bending and shear
Bearing and bending
Bearing, shear and bending
In a tension member if one or more than one rivet holes are off the line, the failure of the member depends upon:
Pitch
Gauge
Diameter of the rivet holes
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
In case of plastic design, the calculated maximum shear capacity of a beam as per IS: 800 shall be
0.55 Aw.fy
0.65 Aw.fy
0.75 Aw.fy
0.85 Aw.fy Where, Aw = effective cross-sectional area resisting shear fy = yield stress of the steel
If p and d are pitch and gross diameter of rivets, the efficiency (η) of the riveted joint, is given by
η = p/p - d
η = p/p + d
η = p - d/p
η = p + d/p
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
Pick up the correct statement from the following:
When the gauge distance is larger than the pitch, the failure of the section may occur in a zig-zag line
When the gauge distance is smaller than the pitch, the failure of the section may occur in a straight right angle section through the centre of rivet holes
When the gauge distance and pitch are both equal, the failure to the section becomes more likely as the diameter of the holes increases
All the above
For a single section used as a tension member, the given area is assumed
20% to 30% in excess of the net area
30% to 40% in excess of the net area
40% to 50% in excess of the net area
50% to 60% in excess of the net area