To minimize the total cost of a roof truss, the ratio of the cost of truss to the cost of purlins shall be
1
2
3
4
Correct Answer :
B. 2
Related Questions
When the axis of load lies in the plane of rivet group, then the most heavily loaded rivet will be the one which (Where, Fa is the load shared by each rivet due to axial load and Fm is the shearing load due to moment in any rivet.)
Is at the maximum distance from CG of the rivet group
Is at the minimum distance from CG of the rivet group
Gives the maximum angle between the two forces Fa and Fm
Gives the minimum angle between the two forces Fa and Fm
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 %
For a rectangular section, the ratio of the maximum and average shear stresses, is
1.5
2.0
2.5
3.5
The effective length of a battened column is increased by
5 %
10 %
15 %
20 %
The main type of butt joints, is a double cover
Shear riveted joint
Chain riveted joint
Zig-zag riveted joint
All the above
The deflection of beams may be decreased by
Increasing the depth of beam
Increasing the span
Decreasing the depth of beam
Increasing the width of beam
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
As per IS: 800, in the plastic design, which of the following pairs are correctly matched?
Working Loads Load factor
(i) Dead load 1.7
(ii) Dead Load + imposed load 1.7
(iii) Dead load + load due to wind or 1.3 seismic forces
(iv) Dead load + imposed load + load 1.7 due to wind or seismic forces
Of these statements
(i) and (ii) are correct
(i), (ii) and (iii) are correct
(ii) and (iii) are correct
Only (i) is correct
The mechanism method of plastic analysis satisfies
Equilibrium and mechanism conditions
Equilibrium and plastic moment conditions
Mechanism and plastic moment conditions
Equilibrium condition only
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
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
Pitch of tacking rivets, when double angles connected back to back and acting as tension members should not be more than
500 mm
600 mm
1000 mm
300 mm
The statical method of plastic analysis satisfies
Equilibrium and mechanism conditions
Equilibrium and plastic moment conditions
Mechanism and plastic moment conditions
Equilibrium condition only
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
In factory buildings, the horizontal beams spanning between the wall columns supporting a wall covering, are called
Stringers
Trimmers
Girts
Lintels
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
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
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
On steel structures the dead load is the weight of
Steel work
Material fastened to steel work
Material supported permanently
All the above
A riveted joint may experience
Shear failure
Shear failure of plates
Bearing failure
All the above
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
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
If d is the distance between the flange angles, the vertical stiffeners in plate girders are spaced not greater than
d
1.25 d
1.5 d
1.75 d
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
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)
Bolts are most suitable to carry
Shear
Bending
Axial tension
Shear and bending
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
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
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 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