APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
First Semester M.Tech. Degree Examination, December 2015
CIVIL ENGINEERING
(STRUCTURAL ENGINEERING)
01 CE 6105 - Structural Dynamics
Time : 3 hrs. Max. marks : 60
PART A
(Answer any TWO questions)

1.a. What are the various components of a vibratory system and develop the equation
of motion for a single degree of freedom system. (5)

b. Determine the natural frequency and natural period of vibration of a portal
frame with one end fixed and other end hinged having ೩ mass of 50 KN
lumped at the floor level. E = 2x1 0° N/mm 2 , I 15x10 गा) +, Storey height
= 3.5 m (4)

2. a. A mass of 100 kg is subjected to vibration excited by a harmonic force of
amplitude 80 N at 3 Hz. If the stiffness of the system is 30 KN/m and damping
coefficient is 1000 Nsec/m, write down the differential equation of motion and
find out the amplitude of displacement and phase angle. (6)

0. Explain any one method for the evaluation of damping in a structural system.

(3)

3. a. Derive the expression for the response of an undamped system subjected to a
blast load varying in the form of a ramp using Duhamel integral. Hence, evaluate
the deflection of the tower at 0.06 sec., if the mass and stiffness of the tower are
400 KN and 40 kKN/mm respectively. The maximum value of load is 300 KN at
0.1 sec. (6)

b. Explain how the response of a system subjected to a periodic loading can be
determined. (3)

PART B
(Answer any TWO questions)
4. a. Explain the role of tuned mass dampers in vibration control. (3)

b. Differentiate between lumped and consistent mass matrices for a structural

system. (3)