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)
Correct Answer :
B. Both (i) and (ii)
Related Questions
The permissible stress in bending for rolled steel I-beams and channels, is
1500 kg/cm2
1575 kg/cm2
945 kg/cm2
1650 kg/cm2
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
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
Rolled steel beams are:
Mainly used to resist bending stress
Used as independent sections to resist compressive stress
Used as independent sections to resist tensile stress
All the above
Shape factor is a property which depends
Only on the ultimate stress of the material
Only on the yield stress of the material
Only on the geometry of the section
Both on the yield stress and ultimate stress of material
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
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 ratio of plastic section modulus to elastic section modulus
Is equal to 1
Is always less than 1
Is always greater than 1
Can be less than 1
On steel structures the dead load is the weight of
Steel work
Material fastened to steel work
Material supported permanently
All the above
The critical stress on a column for elastic buckling given by Euler's formula, is
fc = π²E/(I/r)²
fc = (I/r)²/ πE
fc = (I/r)/ πE
fc = π²E/(I/r)
Other conditions being same, the load factor in indeterminate structures is
Equal to load factor in determinate structures
More than the load factor in determinate structures
Less than the load factor in determinate structures
Unpredictable
If d is the distance between the flange angles of a plate girder, vertical stiffeners are provided at a distance not greater than
d but not less than 0.20 d
1.25 d but not less than 0.33 d
1.5 d but not less than 0.33 d
2.0 d but not less than 0.50 d
The least permissible clear dimension of the web of thickness t in the panel of a plate girder, is restricted to
150 t
160 t
170 t
180 t
The minimum thickness of a steel plate, which is directly exposed to weather and is not accessible for cleaning and repainting, should be:
4.5 mm
6 mm
8 mm
10 mm
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
For determination of allowable stress in axial compression, Indian Standard Institution has adopted
Euler's formula
Rankine formula
Perry Robertson formula
Secant formula
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 circular column section is generally not used in actual practice because
It is uneconomical
It cannot carry the load safely
It is difficult to connect beams to the round sections
All of the above
The bending moment for filler joists at the middle of an intermediate span, is
WL²/10
- WL²/10
- WL²/12
WL²/12
If the loaded length of span in meters of a railway steel bridge carrying a single track is 6 m, then impact factor is taken as
0
0.5
Between 0.5 and 1.0
1.0
The ratio of longitudinal stress to strain within elastic limit, is known as
Modulus of elasticity
Shear modulus of elasticity
Bulk modulus of elasticity
All the above
Web crippling generally occurs at the point where
Bending moment is maximum
Shearing force is minimum
Concentrated loads act
Deflection is maximum
The load on a lintel is assumed as uniformly distributed if the height of the masonry above it, is upto a height of
The effective span
1.25 times the effective span
1.50 times the effective span
2.0 times the effective span
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
Effective length of a column effectively held in position and restrained in direction at both ends, is
L
0.67 L
0.85 L
1.5 L
The internal pressure coefficient on walls for buildings with large permeability is taken as
± 0.2
±0.5
± 0.7
0
A beam may be designed as a cased beam if
Section is of double open channel form with the webs not less than 40 mm apart
Overall depth and width of the steel section do not exceed 750 and 450 mm respectively
Beam is solidly encased in concrete with 10 mm aggregate having 28 days strength 160 kg/cm2
All the above
A column splice is used to increase
Length of the column
Strength of the column
Cross-sectional area of the column
None of these
Stiffeners are used in a plate girder
To reduce the compressive stress
To reduce the shear stress
To take the bearing stress
To avoid bulking of web plate
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