Andhra University 2008 B.E STRENGTH OF MATERIALS - exam paper
Wednesday, 01 May 2013 03:05Web
STRENGTH OF MATERIALS
Chemical Engineering
Time : 3 hours Maximum : 75 Marks
ques. one is compulsory
ans any 4 from ques. two to 8
All ques. carry marks
20
b) A 0.12 mm diameter steel rod AB is fitted to a round hole
near end C of the wooden member CD. For the loading
shown, determine the maximum avg. normal stress in tbe
wood (Figure 2) (8 Marks)
Q.3
The five kN load P is supported by 2 wooden members of
uniform cross part that are joined by the simple glue.
Determine the normal and shearing stresses in the glued surface
(Figure 3) (15 Marks)
Q.4
For the beam and loading shown, draw the Shear force and
Bending moment diagrams (Figure 4) (7 Marks)
b) Draw the Shear force Diagram and Bending moment
diagrams for the beam loaded as shown. (Figure 5)
(8 Marks)
(Figure 3)
21
Q.5
a) The assembly shown consists of an aluminium shell with
(Ea=70GPa,aa=23.6 ´ 10-6/ 0C) fully bonded to a steel
core (Es=200GPa,as=11.7 ´ 10-6/ 0C) and is unstress
-ed at temperature 200C. Considering only axial deformations,
determine the stress in the aluminium shell when the temperature
reaches 1800C. (Figure 6)
b) The 1.5 m concrete post is reinforced with 6 steel bars, every
with a 28-mm diameter. provided that ES = 200 GPa, and
EC = 25 GPa, determine the normal stresses in the steel and in
the concrete when a 1550 kN axial centric force P is applied to
the post (Figure 7)
(Figure 5)
22
Q.6
a) The torques shown are exerted on pulleys A,B,C. The shafts
are solid. Determine the maximum shearing stress in a) Shaft
AB and b) Shaft BC (Figure 8)
b) The allowable shearing stress is 100 MPa in the 36-mm diameter
part AB and 60 MPa in the 40-mm diameter part BC.
Neglecting the effect of stress concentrations, determine the
largest torque that can be applied at A.(Figure 9)
23
Q.7
At a point in a strained material the vertical shear stress is 15
MPa and the horizontal tensile stress is 25 MPa. Using Mohr’s
circle method obtain the principal stresses and direction of the
principal of the principal planes (15 Marks)
Q.8
a) A safety value of eight cm diameter is to blow off at a pressure of 1
N/mm2 gauge. It is held by a closed coil helical spring of circular
steel wire. The mean diameter is 15 cm and the initial compression
is 2cm. obtain the diameter of the steel wire and the number of
coils necessary if the shear stress allowed is 80 N/mm2.
(5 Marks)
b) A thin spherical shell 50 cm in diameter with a thickness three mm is
full of water at atmospheric pressure (0.1 MPa). obtain the intensity
of radial pressure exerted on the wall of the shell if 30 cc of
water at atmospheric pressure is pumped into the shell. compute
the resulting hoop stress and the change in quantity of sphere if E
= 210 GPa, m=0.33,Kwater=2.361GPa (10 Marks)
Earning: Approval pending. |