For the economical design of a combined footing to support two equal column loads, the projections of beams in lower tier are kept such that bending moment under column is equal to
Bending moment at the centre of the beam
Half the bending moment at the centre of the beam
Twice the bending moment at the centre of the beam
None of these
Correct Answer :
A. Bending moment at the centre of the beam
Related Questions
Rolled steel Tee-sections are used
As columns
With flat strips to connect plates in steel rectangular tanks
As built up sections to resist axial tension
None of these
For eccentrically loaded columns, the bending factor is
Cross-sectional area of column/Radius of gyration
Radius of gyration/Cross-sectional area of column
Cross-sectional area of column/Section modulus of the section
Section modulus of the section/Cross-sectional area of column
If the depth of the section of an upper column is smaller than the lower column
Filler plates are provided with column splice
Bearing plates are provided with column splice
Filler plates and bearing plates are provided with column splice
None of these
A simply supported beam carrying a central load, will be safe in deflection if the ratio of its span to depth, is
< 19
< 24
> 19
> 24
The most commonly used sections in lateral system to carry shear force in built up columns, are
Rolled steel flats
Rolled angles
Rolled channels
All the above
The maximum permissible slenderness ratio of a member carrying loads resulting from wind, is
180
200
250
300
Bolts are most suitable to carry
Shear
Bending
Axial tension
Shear and bending
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 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
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
Allowable working stress corresponding to the slenderness ratio of double angles placed back to back and connected to one side of a gusset plate, is reduced to
50 %
60 %
70 %
80 %
The capacity of the smallest pressed steel tank is
1000 litre
1650 litre
1950 litre
2450 litre
A fillet weld may be termed as
Mitre weld
Concave weld
Convex weld
All the above
The main assumption of the method of simple design of steel frame work, is:
Beams are simply supported
All connections of beams, girders and trusses are virtually flexible
Members in compression are subjected to forces applied at appropriate eccentricities
All the above
A structural member subjected to compressive stress in a direction parallel to its longitudinal axis, is generally known as
Column
Stanchion
Post
All the above
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
For steel members exposed to weather and not accessible for repainting, the thickness of steel should not be less than
4.5 mm
6 mm
8 mm
10 mm
The effective length of a battened strut effectively held in position at both ends but not restrained in direction is taken as
1.8 L
L
1.1 L
1.5 L
The mechanism method of plastic analysis satisfies
Equilibrium and mechanism conditions
Equilibrium and plastic moment conditions
Mechanism and plastic moment conditions
Equilibrium condition only
Gantry girders are designed to resist
Lateral loads
Longitudinal loads and vertical loads
Lateral, longitudinal and vertical loads
Lateral and longitudinal loads
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
As per IS : 800, for compression flange, the outstand of flange plates should not exceed
12 t
16 t
20 t
25 t Where t = thickness of thinnest flange plate
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
2.Compression members composed of two channels back-to-back and separated by a small distance are connected together by riveting so that the minimum slenderness ratio of each member between the connections, does not exceed
40
50
60
70
The forces acting on the web splice of a plate girder are
Axial forces
Shear and axial forces
Shear and bending forces
Axial and bending forces
Efficiency of a riveted joint, having the minimum pitch as per IS : 800, is
40 %
50 %
60 %
70 %
On steel structures the dead load is the weight of
Steel work
Material fastened to steel work
Material supported permanently
All the above
The method of design of steel framework for greatest rigidity and economy in weight, is known as
Simply design
Semi-rigid design
Fully rigid design
None of these
A compression member consisting of angle sections may be a
Continuous member
Discontinuous single angle strut
Discontinuous double angle strut
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