SATHYABAMA UNIVERSITY
(Established under section 3 of UGC Act, 1956)
Course & Branch: B.E-P-CIVIL
Title of the Paper: Strength of Materials Max. Marks: 80
Sub. Code: SMEX1010 Time: 3 Hours
Date: 06/12/2010 Session: FN
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PART - A (10 X 2 = 20)
Answer ALL the Questions
1. Define Hooke’s law.
2. What is meant by resilience?
3. Name the different types of beams.
4. Define point of contraflexure.
5. State the theory of simple bending.
6. What is meant by strength of a section?
7. What are the methods used to find the slope and deflection at a section?
8. What is the use of moment area method?
9. What are the two types of tensile stresses which occur in a cylindrical shell?
10. What are the assumptions made in the Lame’s theory?
PART – B (5 x 12 = 60)
Answer ALL the Questions
11. (a) A hollow steel tube 3.5 m long has external diameter of 120mm. The tube was subjected to a tensile load of 400 kN and extension was measured to be 2mm. If the modulus of elasticity for the tube material is 200 GPa. Determine the internal diameter of the tube. (8)
(b) What is the principle of the superposition and mention its applications? (4)
(or)
12. A steel rod ABC is firmly held between two rigid supports at A and C as shown in Fig. Find the stresses developed in the two portions of the rod, when it is heated through 15°K. Take a = 12 x 10-6/°K and E = 200 GPa.
13. A cantilever beam of 1.5 m span is loaded as shown in Fig.2. Draw the shear force and bending moment diagrams.
(or)
14. A beam ABCD 4m long is overhanging by 1m and carries load as shown in Figure. 3. Draw the shear force and bending moment diagrams for the beam and locate the point of contraflexure.
15. A cantilever beam with a rectangular cross section having 80mm width and 120mm depth. If the cantilever is subjected to a point load of 6 kN at the free end and the bending stress is not to exceed 40 MPa. Find the span of the cantilever beam.
(or)
16. An I-section, with rectangular ends has the following dimensions: Flanges = 150mm x 20mm, Web = 300mm x 10mm. Find the maximum shearing stress developed in the beam for a shear force of 50 kN.
17. A beam of rectangular section has a span of 4.8 m and is simply supported at its ends. It is required to carry a total load of 45 kN uniformly distributed over the whole span. Find the values of the breadth (b) and depth (d) of the beam. If the maximum bending stress is not to exceed 7 MPa and maximum deflection is limited to 90.5 mm. Take E value of the beam as 10.5 GPa.
(or)
18. A simply supported beam AB of 2.8 m span carries a point load of 60 kN at a distance of 1m from the left hand support A. What is the position of the maximum deflection of the beam? Also find the magnitude of the deflection under the load. Take the EI value of the beam section as 4 x 1012 N-mm2.
19. A cylindrical vessel 2m long and 500mm in diameter with 10mm thick is subjected to an internal pressure of 3 MPa. Calculate the change in volume of the vessel. Take the E value as 200 GPa and Poisson’s ratio as 0.3 for the material.
(or)
20. A thick metallic cylindrical shell of 150 mm internal diameter is required to with stand an internal pressure of 8N/mm2. Find the necessary thickness of the shell, if the permissible tensile stress in the section is 20 N/mm2.