The effective length of a compression member of length L, held in position and restrained in direction at both ends, is
L
0.67 L
0.85 L
1.5 L
Correct Answer :
B. 0.67 L
Related Questions
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 diameter of a bolt hole is taken as the nominal diameter of the bolt plus
1.0 mm
1.2 mm
1.4 mm
1.6 mm
The effective length of a compression member of length L held in position and restrained in direction at one end and effectively restrained in direction but not held in position at the other end, is
L
0.67 L
0.85 L
1.5 L
If the unsupported length of a stanchion is 4 metres and least radius of gyration of its cross-section is 5, the slenderness ratio of the stanchion, is
60
70
80
100
The main advantage of a steel member, is:
Its high strength
Its gas and water tightness
Its long service life
All the above
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
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
If d is the distance between the flange angles, the vertical stiffeners in plate girders without horizontal stiffeners, are spaced at a distance not less than
0.15 d
0.22 d
0.33 d
0.44 d
The allowable shear stress in the web of mild steel beams decreases with
Decrease in h/t ratio
Increase in h/t ratio
Decrease in thickness
Increase in height Where 'h' is height and t is thickness
A tension member, if subjected to possible reversal of stress due to wind, the slenderness ratio of the member should not exceed
180
200
300
350
The use of tie plates in laced columns is
Prohibited
Not prohibited
Permitted at start and end of lacing system only
Permitted between two parts of the lacing
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
Minimum thickness of web in a plate girder, when the plate is accessible and also exposed to weather, is
5 mm
6 mm
8 mm
10 mm
A major beam in a building structure, is known as
A girder
A floor beam
A main beam
All the above
The actual thickness of butt weld as compared to the thickness of plate is usually
More
Less
Equal
None of the above
Angle of inclination of the lacing bar with the longitudinal axis of the column should preferably be between
10° to 30°
30° to 40°
40° to 70°
90°
If the pitch is 6 cm and rivet value is 4 tonnes, the number of rivets required for a riveted connection carrying an eccentric load of 15 tonnes at a distance of 30 cm from the centre line, is
6
8
10
15
The maximum permissible span of asbestos cement sheets is
650 mm
810 mm
1250 mm
1680 mm
The greatest permissible clear dimension of the web of thickness t in the panel of a plate girder, is restricted to
180 t
220 t
230 t
270 t
The bending moment for filler joists at the middle of an intermediate span, is
WL²/10
- WL²/10
- WL²/12
WL²/12
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
Which of the following conditions is to be satisfied both in elastic and plastic analysis?
Equilibrium condition
Yield condition
Plastic moment condition
Mechanism condition
The maximum tensile and compressive bending stress in extreme fibres of rolled I-sections and channels on the effective section, is
1500 kg/cm2
1420 kg/cm2
1650 kg/cm2
2285 kg/cm2
The greatest gauge of long rivets should not exceed (where d is the diameter of the holes).
2 d
4 d
6 d
8 d
A column splice is used to increase
Length of the column
Strength of the column
Cross-sectional area of the column
None of these
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
A riveted joint many experience
Tearing failure of plates
Splitting failure of plates at the edges
Bearing failure of rivets
All the above
To the calculated area of cover plates of a built-up beam, an allowance for rivet holes to be added, is
10 %
13 %
15 %
18 %
Assuming the values of maximum deviation ΔP and ΔE to be 25% of the computed value of P and E respectively, the minimum value of the factor of safety is
1.00
0.67
1.67
2.67
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