SRS Quick Start
SOFTWARE USER MANUAL
2. Introduction
Mechanical shock pulses are often analysed in terms of shock response spectrum. The shock response
spectrum assumes that the shock pulse is applied as a base input to an array of independent
single-degree-of-freedom systems. SDOF system assumes that each system has its own natural
frequency. The shock response spectrum gives the peak response of each system.
3. Shock response spectrum model
The shock response spectrum is a calculated function based on the acceleration time history. It applies
an acceleration time history as an excitation to an array of single degree-of freedom (SDOF) systems.
Each system is assumed to have no mass-loading effect on the base input.
Figure 1: Shock response spectrum model
Ÿ is the base input for each system, and
Ẍ
is the absolute response of each system to the input
(double-dot denotes the acceleration). M is the mass, C is the damping coefficient, and K is the stiffness
for each system. Natural frequency for each system is marked with f.
4. DewesoftX ® SRS plugin
a) Input signal
The input signal in the SRS plugin is an impulse shock time signal, usually measured with an
accelerometer.
SRS Shock Response Spectrum V21-1
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