JNTU Kakinada B-Tech 1-2 R1621013 STRENGTH OF MATERIALS – I (Civil Engineering) R16 May 2018 Question Paper

Code No: R1621013
II B. Tech I Semester Supplementary Examinations, May – 2018
STRENGTH OF MATERIALS – I (Civil Engineering)Time: 3 hours Max. Marks: 70
Note: 1. Question Paper consists of two parts (Part-A and Part-B) 2. Answer ALL the question in Part-A
3. Answer any FOUR Questions from Part-B
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PART ?A
1. a)Define (i) Poisson?s ratio and (ii) Volumetric strain (2M)
b) Find the SF at left support, if a simply supported beam of span 6m is
subjected an eccentric point load of 9 kN at distance of 2 m from the left
support. (2M)
c)Write the theory of simple bending equation with usual notation. (2M)
d)Write the shear stress equations and explain the terms. (2M)
e) Find the slope for a cantilever beam of span L, loaded with a UDL of w
kN/m for the whole span. (3M)
f) Deduce the longitudinal stress for a thin spherical shell subjected to an
internal pressure (3M)
PART -B
2. a) Deduce the total extension of a uniformly tapering rod of diameters d and D
over a length of L, when the rod is subjected to an axial load P. (4M)
b) A steel rod of 3 cm diameter and 5 m long is connected to two grips and the
rod is maintained at a temperature of 95
0
C. Determine the stress and pull,
when the temperature falls to 30
o
C, if (i) the ends do not yield and (ii) the
ends yield by 0.12 cm. E=2×10
5
N/mm
2
and a =12×10
-6
/
o
C. (10M)
3. Draw the S.F and B.M diagrams of the beam shown in figure 1.
60kN 40 kN
10 kN/m

A 2m 4 m 4m B
Figure 1

4. a)Write the assumptions made in the theory of simple bending. (4M)
b) A water main 80 cm diameter contains water at a pressure head of 100 m. If
the density of water is 9810 N/m
3
, find the thickness of the metal required
for the water main. Given the permissible stress as 20 N/mm
2
. (10M)
5. a)Derive the shear stress formula from fundamentals. (6M)
b) A 120 mm x 50 mm I-Section is subjected to a shearing force of 15kN.
Calculate the shear stress at the neutral axis and at the top of the web. Given
I = 220×10
4
mm
4
, Area = 9.4×10
2
mm
2
, web thickness = 3.5 mm and flange
thickness = 5.5 mm. (8M)
1 of 2
SET – 1
R16

Code No: R1621013
II B. Tech I Semester Supplementary Examinations, May – 2018
STRENGTH OF MATERIALS – I (Civil Engineering)Time: 3 hours Max. Marks: 70
Note: 1. Question Paper consists of two parts (Part-A and Part-B) 2. Answer ALL the question in Part-A
3. Answer any FOUR Questions from Part-B
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PART ?A
1. a)Define (i) Poisson?s ratio and (ii) Volumetric strain (2M)
b) Find the SF at left support, if a simply supported beam of span 6m is
subjected an eccentric point load of 9 kN at distance of 2 m from the left
support. (2M)
c)Write the theory of simple bending equation with usual notation. (2M)
d)Write the shear stress equations and explain the terms. (2M)
e) Find the slope for a cantilever beam of span L, loaded with a UDL of w
kN/m for the whole span. (3M)
f) Deduce the longitudinal stress for a thin spherical shell subjected to an
internal pressure (3M)
PART -B
2. a) Deduce the total extension of a uniformly tapering rod of diameters d and D
over a length of L, when the rod is subjected to an axial load P. (4M)
b) A steel rod of 3 cm diameter and 5 m long is connected to two grips and the
rod is maintained at a temperature of 95
0
C. Determine the stress and pull,
when the temperature falls to 30
o
C, if (i) the ends do not yield and (ii) the
ends yield by 0.12 cm. E=2×10
5
N/mm
2
and a =12×10
-6
/
o
C. (10M)
3. Draw the S.F and B.M diagrams of the beam shown in figure 1.
60kN 40 kN
10 kN/m

A 2m 4 m 4m B
Figure 1

4. a)Write the assumptions made in the theory of simple bending. (4M)
b) A water main 80 cm diameter contains water at a pressure head of 100 m. If
the density of water is 9810 N/m
3
, find the thickness of the metal required
for the water main. Given the permissible stress as 20 N/mm
2
. (10M)
5. a)Derive the shear stress formula from fundamentals. (6M)
b) A 120 mm x 50 mm I-Section is subjected to a shearing force of 15kN.
Calculate the shear stress at the neutral axis and at the top of the web. Given
I = 220×10
4
mm
4
, Area = 9.4×10
2
mm
2
, web thickness = 3.5 mm and flange
thickness = 5.5 mm. (8M)
1 of 2
SET – 1
R16

Code No: R1621013

6. a)State the moment area theorems. (6M)
b) A simply supported beam of span L, carrying a point load P at 0.3L from
left support. Determine the mid-span displacements and slopes at the
supports, using the method of integration. (8M)
7. A compound cylinder is made by shrinking a cylindrical of external
diameter 300 mm and internal diameter of 250 mm over an another
cylindrical of external diameter 250 mm and internal diameter 200 mm. The
radial pressure at the junction after shrinking is 8 N/mm
2
. Find the final
stresses sent up across the section, when the compound cylinder is subjected
an internal fluid pressure of 84.5 N/mm
2
. (14M)

2 of 2
SET – 1
R16