B.Tech IV (Fourth) Semester Examination 2015-16
Course Code: ECE403
Paper ID: 0964404
Structure Analysis-I
Time: 3 Hours
Max. Marks: 70
Note: Attempt six questions in all. Q. No. 1 is compulsory.
1.
a)
b)
c)
d)
e)
f)
Answer any five of the following (limit your answer to 50
words).
(4x5=20)
Write an expression for end moment for fixed beam of span L
and acted upon a point load ‘w’ at a distance ‘a’ from right hand
support.
Draw a neat influence line diagram for bending moment at a
section 3 m from one end of a simply supported beam which is
12 m long. Calculate also the maximum bending moment at this
section due to a uniformly distributed rolling load 5 m long of 2
kN/m intensity.
Calculate the distributed moments for the members OA, OB,
OC and OD meeting at a point O. If their lengths are 150, 200,
100 and 200 cm and moments of Inertia are 300, 400, 300 and
200 cm4 uits respectively. The applied moment at the joint O is
8100 N cm. Support A and C are hinged while support B and D
are fixed one.
Write a note on principles of virtual work for deflection.
Discuss two propositions that we get while solving beam hinged
at one end and fixed at the other end by using moment
distribution method.
Tabulised distribution factors for the continuous beam shown in
figure below.
g) Write slope deflection equations for the equal span AB and BC
for a beam ABC 10 m long, fixed at end A and C and
continuous over joint B and is loaded with a point load 5kN at 3
m from joint A and 8 kN at mid span of beam BC. This beam
has constant EI for both the spans.
h) Differentiate Kani’s method with the moment distribution
method for analyzing portal frame.
2.
Derive the generalized theorem of three moments. Also
illustrate all four special cases consider for the three moments
theorem.
(10)
3.
Plot the maximum bending moment diagram for a simply
supported girder with the following data:
W1 = 3 kN (leading)
W2 = 6 kN
D = 6 m; L=10 m. Prove that maximum bending moment occurs
under W2 when W1 is of the span.
(10)
4.
A portal frame ABCD is fixed at A and D and has rigid joint at
B and C. The column AB is 3 m long and column CD is 2 m
long. The beam BC is 2 m long and is loaded with UDL of
intensity 6 kN/m. The moment of inertia of AB is 21 and that of
BC and CD is I. Plot bending moment diagram and sketch the
deflected shape of the frame.
(10)
5.
The portal frame ABCD which is hinged at A and fixed at end
D and the joints B and C are rigid. The column CD is subjected
to a horizontal loading of 2 kN/m. A concentrated load of 6 kN
acts on BC at 1 m from B. Length AB is 3 m and moment of
inertia of AB is 1.5 I;, Length BC is 2 m and moment of inertia
of BC is I; Length CD is 4 m and moment of inertia of CD is I.
Analyse the frame completely and sketch its deflected shape by
using
moment
distribution
method.
(10)
6.
A continuous beam ABCD , 12 m long is fixed at A and D and
is loaded as shown in figure below. Analyse the beam
completely if the following movement take place
simultaneously.
i)
The end A yields, turning through 1/250 radians in a
clockwise direction.
ii)
End B sinks by 30 mm in downward direction.
iii)
End C sinks 20 mm in downward direction
The beam has constant I = 38.20 x 105 mm4 and E = 2 x 105
N/mm2.
(10)
7.
Figure below shows the outline of truss used for lifting a load
which is distributed as 2 kN on each of the four points Q, R, S
and T. The members PQ, PR, PS and PT, each have an area of
65 sq mm and the members QR, RS and ST each have of 130 sq
mm. Determine the vertical deflection of Q and R relative to
support P. Take E = 2 x 105 N/mm2 .
(10)
8.
Draw the bending moment diagram and sketch the deflection
shape of the frame by using Kani’s method.
(10)