Response spectrum

A response spectrum is a diagram that describes the response ( = Reply ), a ( idealized ) damped mass oscillator or a plurality of single-degree- in a defined oscillation excitation of their base support points as a function of frequency. The answer may be a displacement, velocity or acceleration. Accordingly, there is displacement, velocity and acceleration response spectra.

Response spectra are required in the design of structures for exposure to earthquakes, for example, by means of modal analysis. Of the spectrum one can read the response of the structure which is to be expected from an excitation by one of its natural frequencies.

Response spectra are derived from the records of many earthquakes, and in a simplified form in standards provided (eg DIN 4149 ) are available.