Extreme response spectrum

Certain theory

The Extreme Response Spectrum (ERS) is defined as a curve giving the value of the highest peak of the response of a linear Single Degree of Freedom System to vibration, according to its natural frequency, for a given damping ratio. The response is described here by the relative movement of the mass of this system in relation to its support. The x-axis refers to the natural frequency and the y-axis to the highest peak multiplied by the square of the quantity, by analogy with the relative displacement shock response spectrum.

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