A counterrotating eccentric mass exciter as shown below is used to determine the Problem 2. vibrational characteristics of a structure of mass M kg. At a speed N rpm, a stroboscope shows the eccentric masses to be at the top at the instant the structure is moving upward through its static equilibrium position, and the corresponding amplitude of vibration is X m. If the unbalance of each wheel of the exciter is em kg-m, determine the following (a) The natural frequency of the structure. (b) Dimensionless damping ratio of the structure. (c) The amplitude of vibration at 1.5N rpm and the angular position of the eccentrics at the instant the structure is moving upward through its equilibrium position. k www www

A counterrotating eccentric mass exciter as shown below is used to determine the Problem 2. vibrational characteristics of a structure of mass M kg. At a speed N rpm, a stroboscope shows the eccentric masses to be at the top at the instant the structure is moving upward through its static equilibrium position, and the corresponding amplitude of vibration is X m. If the unbalance of each wheel of the exciter is em kg-m, determine the following (a) The natural frequency of the structure. (b) Dimensionless damping ratio of the structure. (c) The amplitude of vibration at 1.5N rpm and the angular position of the eccentrics at the instant the structure is moving upward through its equilibrium position. k www www

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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