Tacking rivets in compression plates not exposed to the weather, have a pitch not exceeding 300 mm or
16 times the thickness of outside plate
24 times the thickness of outside plate
32 times the thickness of outside plate
36 times the thickness of outside plate
Correct Answer :
C. 32 times the thickness of outside plate
Related Questions
When a tension member consists of two channel sections, the allowance for rivet hole is made for two holes from
Each web
Each flange
Each web or one hole from each flange whichever is more
Each web or one hole from each flange whichever is less
The web crippling due to excessive bearing stress can be avoided by
Increasing the web thickness
Providing suitable stiffener
Increasing the length of the bearing plates
None of the above
The actual thickness of butt weld as compared to the thickness of plate is usually
More
Less
Equal
None of 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
Steel tanks are mainly designed for
Weight of tank
Wind pressure
Water pressure
Earthquake forces
For a standard 45° fillet, the ratio of size of fillet to throat thickness is
1 : 1
1 : √2
√2 : 1
2 : 1
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
With usual notations of the letters, the shear stress fs at any point of the cross-section is given by
fs =FQ/It
fs =Ft/IQ
fs =It/FQ
fs =IF/Qt
The difference between gross diameter and nominal diameter for the rivets up to 25 mm diameter is
1.0 mm
1.5 mm
2.0 mm
2.5 mm
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
Intermediate vertical stiffeners in a plate girder need be provided if the depth of web exceeds
50 t
85 t
200 t
250 t Where t is thickness of web
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
In a truss girder of a bridge, a diagonal consists of mild steel flat 4001.S.F. and carries a pull of 80 tonnes. If the gross-diameter of the rivet is 26 mm, the number of rivets required in the splice, is
6
7
8
9
Lug angle is
Used with single angle member
Not used with double angle member
Used with channel member
All the above
For a steel grillage footing to support two unequal column loads
Line of action of the resultant of two column loads, is made to coincide with the centre of gravity of the base of the footing
Trapezoidal shape is used for the base footing
Projections of beams on either side in lower tier are such that bending moments under columns are equal
All the above
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
According to IS: 800, in the Merchant Rankine formula the value of imperfection index (n) is
1.0
1.4
1.8
2.0
In the virtual work method, the virtual quantity is
Displacement
Load
Slope
Moment
The allowable tensile stress in structural mild steel plates for steel tank is assumed as
95.0 MPa on net area
105.5 MPa on net area
105.5 MPa on gross area
150.0 MPa on gross area
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
Long column is one
Which is more than 3 m long
Whose lateral dimension is less than 25 cm
Which is free at its top
Which has a ratio of effective length and least lateral dimension more than 15
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
Design of a riveted joint is based on the assumption:
Bending stress in rivets is accounted for
Riveted hole is assumed to be completely filled by the rivet
Stress in the plate in not uniform
Friction between plates is taken into account
The sway bracing is designed to transfer
2Vi % of the top panel wind load to bottom bracing
10% of the top panel wind load to bottom bracing
25% of the top panel wind load to bottom bracing
50% of the top panel wind load to bottom bracing
In case of plastic design, the calculated maximum shear capacity of a beam as per IS: 800 shall be
0.55 Aw.fy
0.65 Aw.fy
0.75 Aw.fy
0.85 Aw.fy Where, Aw = effective cross-sectional area resisting shear fy = yield stress of the steel
If the thickness of plate to be connected by a rivet is 16 mm, then suitable size of rivet as per Unwin's formula will be
16 mm
20 mm
24 mm
27 mm
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 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
If R is the reaction on the bearing plate, the minimum moment of. inertia of the bearing stiffener provided at the support of a plate girder of overall depth D, the maximum thickness of the compression flange T, carrying total load W, is
(D²/250) × (R/W)
(D3T/250) × (R/W)
(DT/250) × (R/W)
(DT/250) × (W/R)
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