This set of Strength of Materials Multiple Choice Questions on “Composite or Flitched Beams”.
1. In flitched beams ______ remains same for both materials.
a) Stress
b) Strain
c) Section modulus
d) Young’s modulus
Answer: b
Clarification: Due to bending, the strain will be same in both the materials.
A timber beam strengthened by steel strips.
Where E of timber / E of steel = m
The equivalent width = b + 2mt.
2. What is the moment due to dead load in case of continuous beams at the middle of interior spans?
a) w L3 / 12
b) w L2/ 14
c) w 3/ 20
d) w L2 / 24
Answer: d
Clarification: The moment due to dead load in case of continuous beams at the middle of interior spans is w L2 / 24.
| Position |
Moment due to dead load |
| Near middle of end span |
W L2/ 12 |
| At the middle of interior span |
W L2/ 24 |
| At the support next to and support |
-W L2/ 22 |
.
3. A continuous beam is one which is _______
a) Infinitely long
b) Supported at two points
c) Supported it more than two supports
d) Supported by a prop
Answer: c
Clarification: A beam which is supported by more than two supports is known as a continuous beam. In this beam, bending moment is low and hence the deflection in the beam is also comparatively less. This beam is stiffer when compared to the other traditional beams.
4. The effective length of column depends upon ________
a) the cross section of beam
b) end conditions
c) maximum bending moment
d) extreme fibres
Answer: b
Clarification: The effective length of column depends upon end conditions.
| End condition |
Effective length |
| Both ends hinged |
L |
| Both ends fixed |
L/2 |
| One end is fixed and other end free |
2L |
5. The phenomenon under which the strain of material varies under constant stress is known as ________
a) Creep
b) Hysteresis
c) Viscoelasticity
d) Strain hardening
Answer: a
Clarification: A creep is a plastic deformation underweight the strain of material where is under constant stress this is one of the mechanical properties of the engineering materials. The best example is the failure of concrete.
6. Volumetric strain = 3× _____ strain.
a) Lateral
b) Linear
c) Composite
d) Yield
Answer: b
Clarification: eV (volumetric strain) = 3× linear strain = 3×e
The volumetric strain is algebraic sum of all the linear(or) axial strain when a solid to be subjected to equal normal sources of the same type of all faces we will have €x, €y and €z equal in value. In this case the volumetric strain will be 3 times the linear strain in any of the three axes.
7. The stress corresponding to breaking point is known as _____________
a) yield stress
b) ultimate stress
c) breaking stress
d) normal stress
Answer: c
Clarification: After reaching ultimate stress, the stress strain curve suddenly falls with rapid increase in strain and specimen breaks. The stress corresponding to breaking point is known as breaking stress and it is denoted by G.
8. Determine the yield stress of a steel rod 20 mm diameter, if the yield load on the steel rod is 88kN.
a) 240.55 N/mm2
b) 280.25 N/mm2
c) 325 N/mm2
d) 290.45 N/mm2
Answer: b
Clarification: Initial area of the Steel rod of 20 mm = 314 mm2 [area of circle]
Yield stress = yield load/ Area
= 88 × 103/ 314
= 280.25 N/mm2.
9. What is the elongation percentage of a steel rod of 50 mm diameter if the total extension is is 54 mm and gauge length is 200 mm.
a) 27%
b) 23%
c) 43%
d) 35%
Answer: a
Clarification: Percentage elongation = Total extension / Gauge length × 100
= 54/200 × 100
= 27%.
10. __________ joints are provided when there is a break in the concreting operation.
a) transverse joints
b) longitudinal joints
c) construction joints
d) warpage joints
Answer: c
Clarification: The construction joints are provided when there is a break in a concreting operation. Although the effort is always made to complete the concrete work in one day, sometimes it is not possible and therefore, construction joints are provided. For beams, the joints should be at the centre of the span or within the middle third.