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
Correct Answer :
B. t = √(64/21)
Related Questions
The minimum pitch of rivet holes of diameter d should not be less than
d
1.25 d
1.5 d
2.5 d
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
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
According to IS: 800-1962, the coefficient of expansion of steel per degree centigrade per unit length, is taken as
0.000008
0.000010
0.000012
0.000014
A single angle in tension is connected by one leg only. If the areas of connecting and outstanding legs are respectively a and b, net effective area of the angle, is
a - [b/{1 + 0.35 (b/a)}]
a + [b/{1 + 0.35 (b/a)}]
a - [b/{1 + 0.2 (b/a)}]
a + [b/{1 + 0.2 (b/a)}]
The effective length of a double angle strut with angles placed back to back and connected to both the sides of a gusset plate, by not less than two rivets, is
0.5 L
0.67 L
0.85 L
2 L
Poisson's ratio for steel within elastic limit, ranges from
0.15 to 0.20
0.25 to 0.24
0.25 to 0.33
0.33 to 0.35
The internal pressure coefficient on walls for buildings with large permeability is taken as
± 0.2
±0.5
± 0.7
0
The rivets which are heated and then driven in the field, are known
Power driven shop rivets
Power driven field rivets
Hand driven rivets
Cold driven rivets
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
Outstanding length of a compression member consisting of a channel, is measured as
Half of the nominal width
Nominal width of the section
From the edge to the first row of rivets
None of these
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
The maximum permissible slenderness ratio of compression member carrying dead and superimposed load, is
180
200
250
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
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
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
Rolled steel beams are designated by Indian Standard series and its
Weight per metre and depth of its section
Depth of section and weight per metre
Width of flange and weight per metre
Weight per metre and flange width
In the virtual work method, the virtual quantity is
Displacement
Load
Slope
Moment
The statical method of plastic analysis satisfies
Equilibrium and mechanism conditions
Equilibrium and plastic moment conditions
Mechanism and plastic moment conditions
Equilibrium condition only
A beam is defined as a structural member subjected to
Axial loading
Transverse loading
Axial and transverse loading
None of these
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
Shear buckling of web in a plate girder is prevented by using
Vertical intermediate stiffener
Horizontal stiffener at neutral axis
Bearing stiffener
None of the above
The least dimension in case of a circular column of diameter D is taken as
0.5 D
0.68 D
0.88 D
D
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 side thrust T on the tie rods provided at the end beam of jack arch of rise R, is calculated from the formula
T = WL/4R
T = WR/8L
T = WL/8R
T = WL/2R
Strengths of a rivet in single shearing, in bearing and in tearing are 3425 kg, 4575 kg and 5025 kg respectively. If the load in the member is 35 tonnes, the number of rivets required, is
10
11
12
13
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
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
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
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