For a compression member with double angle section, which of the following section will give larger value of minimum radius of gyration?
Equal angles back to back
Unequal legged angles with long legs back to back
Unequal legged angles with short legs back to back
Both (B) and (C)
Correct Answer :
B. Unequal legged angles with long legs back to back
Related Questions
According to IS : 800-1962 the permissible bending stress in steel slab plates, is
1500 kg/cm2
1420 kg/cm2
2125 kg/cm2
1890 kg/cm2
When the axis of load lies in the plane of rivet group, then the rivets are subjected to
Only shear stresses
Only tensile stresses
Both (A) and (B)
None of the above
Minimum pitch provided in riveted steel tanks is
1.5 d
2.0 d
2.5 d
3.0 d Where d is diameter of rivets
If P is the wind pressure in kg/cm2, v is the velocity in km/hour and K is a constant of proportionality, then
P = K/v2
v = K/P2
P = Kv2
P = Kv
The beams supporting the steps of a stair are generally known as
Headers
Trimmers
Stringers
Spandrel beams
The effective length of a weld, is taken as the actual length
Minus the size of weld
Minus twice the size of weld
Plus the size of weld
Plus twice the size of weld
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)
The rolled steel I-sections are most commonly used as beams because these provide
Large moment of inertia with less cross-sectional area
Large moment of resistance as compared to other section
Greater lateral stability
All the above
If the thickness of a structural member is small as compared to its length and width, it is classified as
One dimensional
Two dimensional
Three dimensional
None of these
Maximum permissible slenderness ratio of a member normally acting as a tie in a roof truss, is
180
200
250
350
Tacking rivets in tension members, are provided at a pitch in line not exceeding
25 cm
50 cm
75 cm
100 cm
The main type of butt joints, is a double cover
Shear riveted joint
Chain riveted joint
Zig-zag riveted joint
All the above
For the steel member exposed to weather and accessible for repainting, the thickness of steel should not be less than (accepting the webs of Indian Standard rolled steel joists and channels).
4 mm
6 mm
8 mm
10 mm
The ratio of shearing stress to shearing strain within elastic limit, is known as
Modulus of elasticity
Shear modulus of elasticity
Bulk modulus of elasticity
Tangent modulus of elasticity
The most economical section for a column, is
Rectangular
Solid round
Flat strip
Tubular section
If the thickness of thinnest outside plate is 10 mm, then the maximum pitch of rivets in tension will be taken as
120 mm
160 mm
200 mm
300 mm
When a tension member is made of four angles with a plate as a web, the allowance for holes is made as
Two holes for each angle and one hole for the web
One hole for each angle and one hole for the web
One hole for each angle and two holes for the web
Two holes for each angle and two holes for the web
When the length of a tension member is too long
A wire rope is used
A rod is used
A bar is used
A single angle is used
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
In a gusseted base, when the end of the column is machined for complete bearing on the base plate, then the axial load is assumed to be transferred to base plate
Fully by direct bearing
Fully through fastenings
50% by direct bearing and 50% through fastenings
75% by direct bearing and 25% through fastenings
Which of the following sections should preferably be used at places where torsion occurs?
Angle section
Channel section
Box type section
Any of the above
The allowable stress in axial tension is generally kept less if thickness of the member is more than
10 mm
12 mm
15 mm
20 mm
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
Pick up the correct statement from the following:
The slenderness ratio of lacing bars for compression members should not exceed 145
The minimum width of lacing bar connected with rivets of nominal diameter 16 mm, is kept 50 mm
The minimum thickness of a flat lacing bar is kept equal to onefortieth of its length between inner end rivets
All the above
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
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
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
Effective sectional area of a compression member is:
Gross sectional area - area of rivet hole
Gross sectional area + area of rivet hole
Gross sectional area × area of rivet hole
Gross sectional area + area of rivet hole
If the depth of two column sections is equal, then the column splice is provided
With filler plates
With bearing plates
With filler and hearing plates
None of these
Rise of a Jack arch is kept about
1/2 to 1/3 of the span
1/3 to 1/4 of the span
1/4 to 1/8 of the span
1/8 to 1/12 of the span