Download PTU (Punjab Technical University) B.Tech (Bachelor of Technology) / BE (Bachelor of Engineering) 2021 January CE 3rd Sem 76371 Solid Mechanics Previous Question Paper
Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech.(CE) (2018 Batch) (Sem.?3)
SOLID MECHANICS
Subject Code : BTCE-302-18
M.Code : 76371
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
Write briefly :
1.
Explain various types of beams.
2.
What are the various types of stresses? Explain.
3.
What are the various assumptions made in the Euler's theory
4.
Give classification of materials
5.
Explain the terms `Torsional Rigidity'.
6.
What are the limitations of Euler's formula?
7.
Define polar modulus of the shaft section.
8.
Define the term equivalent length. Discuss its uses.
9.
Define columns, Post and struts.
10. What is point of contraflexure?
SECTION-B
11. A load of 300 kN is applied on a short concrete column 250 mm ? 250 mm. The column
is reinforced by steel bars of total area 5600 mm2. If the modulus of elasticity for steel is
15 times that of concrete, find the stress in steel and concrete. If the stress in concrete
should not exceed 4 N/mm2, find the area of steel required so that the column may
support a load of 600 kN.
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12. Two planes AB and BC which are at right angles carry shear stresses of intensity
17.5 N/mm2 while these planes also carry a tensile stress of 70 N/mm2 and a compressive
stress of 35 N/mm2. Determine principal planes and principal stresses. Also determine the
maximum shear stress and the planes on which it acts.
13. A cast iron test beam 20 mm ? 20 mm in section and 1m long and supported at the ends
fails when a central load of 640 N is applied. What uniformly distributed load will break
a cantilever of the same material 50 mm wide, 100 mm deep and 2m long?
14. A square column of wood is 2.5 m long with pinned ends. Taking a factor of safety of 2.5
in computing Euler's critical load and also taking the allowable compressive stress as
12 N/mm2, find the size of the cross section, if the column has to safely support
(i) 150 kN (ii) 275 kN. Take E=1.3 ? 104N/mm2.
15. A thin walled spherical vessel having a diameter of 1.50m is made of steel plates of
uniform thickness. It is filled with water which is pumped in untill the pressure is
1.75 N/mm2. After the pumping has been completed, a relief valve fitted to the vessel is
opened and water is allowed to escape until the pressure falls to atmospheric. If the
volume of water which escapes is 3500 cc, determine the thickness of the plates.
SECTION-C
16. A beam of length L carries a uniformly distributed load of w per unit run on its whole
length. It has one support at its left end and the other support is at a distance `a' from the
other end. Find the value of `a' so that the maximum bending moment for the beam is as
small as possible. Find also the maximum bending moment for this condition.
17. A beam of length L simply supported at the ends carries a point load W at a distance `a'
from the left end. Find the deflection under the load and the maximum deflection. Use
Macaulay's method.
18. Derive the torsion equation and state various assumptions made in the theory of pure
torsion.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
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This post was last modified on 26 June 2021