Structural Mechanics, Question Paper of Civil Engineering 4th Semester, Download Question Paper 6

Roll No­­­­­­­­­_________

STRUCTURAL MECHANICS

5^th Exam /Civil/5162/May’06

                                                             

Duration 3 Hrs.

Section –A

Note : attempt any ten questions.

1.     Fill in the blanks:

a.     Bulk modulus k = _______

b.     A beam whose one end fixed and other end is free is called a ____

c.      _______ is defined as the algebraic sum of moments of all the vertical forces acting on one side of the section.

d.     Unit o radius of gyration is _____

e.      Bending stress is also   known as ______

f.       Shear stress varies along of _________ of the beam.

g.     Slope at any section of a deflected beam in the ____ which the tangent at that section makes with the horizontal.

h.     In the case of _________ maximum deflection will be at the free end.

i.       For no tension in a compression member. The eccentricity must not exceed _______

j.       For a prefect frame the relation between the number of members and number of joints is given by _______

Section –B

Note : attempt any five questions

2.       

a.     Define the terms stress, strain young’s modulus of elasticity. Write relationship between them.

b.     Define a beam. Describe different types of beam.

c.      Define section modulus and radius of gyration.

d.     What is shear stress in beam?

e.      Differentiate between concentric load and a column and their effects on it.

f.       What are the different methods of finding out forces in a perfect frame? Explain any one.

g.     On what factors does the strength of a beam depends.

Section –C

Note : Attempt any three questions

3.     A bar 300 mm long is 50 mm x 50 mm in section for 120 mm of its length, 20 mm dia for 80 mm length and 40 mm dia for the remaining length. If the tensile force of 80 KN is applied to the bar calculate the stresses induced in the different section and total elongation of the bar. Take E=2x10⁵ N/mm²

4.     A simply supported beam of span 9 m carries a u.d.l. of 10 KN/m over the whole span and also two point loads of 15 kN and 20 kN at 6 m and 7.5 m respectively from the left support draw the S.F.D and B.M.D for the beam giving their valves.

5.     An I-section has the following dimensions.

Flanges – 150 mm x 20 mm

Web – 300 mm x 20 mm

If the SF acting on the beam is 100 kN. Determine the shear stress distribution in the beam and draw it.

6.     A wooden plank 300 mm wide and 100 mm deep in section rests on two wooden supports at the same horizontal level which are 4 m apart. A man weighing 800 N stands in the middle of the plank. Find

a.     Max bending stress developed in the plank

b.     Max deflection of plank

7.     A hollow circular column having external and internal diameters of 250 mm respectively carries a vertical load of 120 kN a the outer edge of the column. Calculate the maximum and minimum intensities of stress in the section.