1- A machine and its foundation weight 270 kN. The spring constant (for each spring) and the coefficient of damping (for each dashpot) of the soil supporting the soil be taken as 1800 kN/m and 140 kN-s/m, respectively. Forced vibration of the foundation is caused by a force that can be expressed using following relation (Q = 516 sin 67t (kN) ). Determine the following unknowns: (6 point) Foundation and Machine Spring Dashpot Spring Dashpot Spring Spring a) The undamped natural frequency of the foundation, b) Amplitude of motion, c) Maximum dynamic force transmitted to the subgrade, d) Equation of motion (differential equation the vibratory system), and e) Cumulative displacement of the foundation (Static and Dynamic settlements). Note: Number of springs and dashpots must be taken into consideration.

1- A machine and its foundation weight 270 kN. The spring constant (for each spring) and the coefficient of damping (for each dashpot) of the soil supporting the soil be taken as 1800 kN/m and 140 kN-s/m, respectively. Forced vibration of the foundation is caused by a force that can be expressed using following relation (Q = 516 sin 67t (kN) ). Determine the following unknowns: (6 point) Foundation and Machine Spring Dashpot Spring Dashpot Spring Spring a) The undamped natural frequency of the foundation, b) Amplitude of motion, c) Maximum dynamic force transmitted to the subgrade, d) Equation of motion (differential equation the vibratory system), and e) Cumulative displacement of the foundation (Static and Dynamic settlements). Note: Number of springs and dashpots must be taken into consideration.

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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