Design of Steel Structures MCQs - Tension Members and their Types

1. The strength of tensile members is not influenced by :
a) length of connection
b) net area of cross section
c) type of fabrication
d) length of plate

Answer: d
Explanation: The strength of tensile members is influenced by factors such as length of connection, size and spacing of fasteners, size and spacing of fasteners, net area of cross section, type of fabrication, connection eccentricity, and shear lag at the end connection

2. Which of the following statement is correct?
a) single angle section with bolted connection produce eccentricity about both planes
b) single angle section with bolted connection produce eccentricity about one plane only
c) single angle section with welded connection produce eccentricity about both planes
d) single angle section with welded connection does not produce eccentricity about one plane

Answer: a
Explanation: Single angle section with bolted connection produce eccentricity about both planes, whereas single angle section with welded connection may produce eccentricity about one plane only.

3. Which of the following statement is correct?
a) Single angle members are used where members are subjected to reversal of stresses
b) Double angle members are used in towers
c) Single angle members are used as web members in trusses
d) Double angle members are used as web members in trusses

Answer: c
Explanation: Single angle members are used in towers and as web members in trusses. Double angle sections are used as chord members in light roof trusses or in situations where some rigidity is required and where members are subjected to reversal of stresses.

4. What is the difference between strand and wire rope?
a) Strand consists of individual wires wound helically around a central core, wire rope is made of several strand laid helically around a core
b) Wire rope consists of individual wires wound helically around a central core, strand is made of several wire ropes laid helically around a core
c) Strand consists of individual wires wound straight around a central core, wire rope is made of several strand laid helically around a core
d) Wire rope consists of individual wires wound straight around a central core, strand is made of several wire ropes laid helically around a core

Answer: a
Explanation: Strand consists of individual wires wound helically around a central core, wire rope is made of several strand laid helically around a core. Wire ropes are exclusively used for hoisting purposes and as guy wires in steel stacks and towers.

5. Which of the following statement is not correct?
a) Cables in form of wires ropes and strands are used in application where high strength is required
b) Cables are generally long and their flexural rigidity is negligible
c) They are flexible
d) They are recommended in bracing systems

Answer: d
Explanation: Cables used as floor suspenders in suspension bridges are made from individual strands wound together in rope like fashion. Cables in form of wires ropes and strands are used in application where high strength is required and flexural rigidity is unimportant. Cables are generally long and their flexural rigidity is negligible. They are flexible. They are not recommended in bracing systems as they cannot resist compression.

6. Bars and rods are not used as :
a) tension members in bracing systems
b) friction resistant members
c) sag rods to support purlin
d) to support girts in industrial buildings

Answer: b
Explanation: Bars and rods are used as tension members in bracing systems, sag rods to support purlin between trusses, to support girts in industrial buildings, where light structure is desirable. Rods are also used in arches to resist thrust of arch.

7.Sagging of members by built up bars and rods may be minimised by
a) increasing length diameter
b) increasing thickness ratio
c) fabricating rod/bar short of its required theoretical length
d) fabricating rod/bar more than its required theoretical length

Answer: c
Explanation: Sagging of members by built up bars and rods may be minimised by limiting length diameter or thickness ratio or by fabricating the rod/bar short of its required theoretical length by some arbitrary amount and drawing into place to provide an initial tension. The same effect may be produced by providing turnbuckle in the rod.

8. Which of the following type of tension member is not mainly used in modern practice?
a) open section such as angles
b) flat bars
c) double angles
d) circular section

Answer: b
Explanation: Tension members were generally made of flat bars earlier. But modern practice is to use mainly the following sections for tension members: (i)open sections such as angles, channels and I-sections, (ii)compound and built up sections such as double angle and double channels with or without additional plates, (iii)closed sections such as circular, square, rectangular or hollow sections

9. Which among the following comparison between angle and flat bars is not true?
a) for light loads, angles are preferred over flat bars
b) flat bar tension members tend to vibrate during passage of load in light bridges
c) flat bars are used instead of angles in case of stress reversal
d) angles are used instead of flat bars in case of stress reversal

Answer: c
Explanation: For light loads, angles are preferred over flat bars. In many light bridges, flat bar tension members tend to vibrate during passage of load. In case of stress reversal angles are more suitable whereas flat bars are unfit to carry compressive load on reversal due to their small radius of gyration in one direction.

10. Which of the following statement is correct?
a) angles placed on same side of gusset plate produce eccentricity about one plane only
b) angles placed on same side of gusset plate produce eccentricity about two planes
c) angles placed on opposite side of gusset plate produce eccentricity about one plane only
d) angles placed on opposite side of gusset plate produce eccentricity about two planes

Answer: a
Explanation: Two angle sections can either be placed back-to-back on the same side of gusset plate, or back-to-back on the opposite side of gusset plate. When angles are connected on the same side of gusset plate, the eccentricity is about one plane only, which can be almost eliminated when the same angles are connected on opposite side of gusset plate.