Guralp-systems Strong Motion Manuel d'utilisateur télécharger pdf (Page 16)

Strong Motion User Guide

RMS (root mean square)

The RMS is computed every second and is the root mean

square of the digital counts for a one-second period. The DC

offset of the signal is removed by subtracting the average from

the MMA calculation. The RMS is a measure of the energy

imparted to the digitiser during a one-second period. The result

is in gal.

SI (spectral intensity)

The spectral intensity is a measurement that attempts to

determine the amount of energy absorbed by structures in the

vicinity of the sensor during an event. The calculation uses a

series of frequency-dependent filters to model structures and

performs an integration calculation to compute the expected

velocity (pseudo-velocity) of these structures.

The result, in kine, is thus an indication of how fast a structure

was moving and thus how likely it is to be damaged. SI

corresponds very closely to physical damage.

16 Issue F

1 2 ... 11 12 13 14 15 16 17

Pas de commentaire

Guralp-systems Strong Motion Manuel d'utilisateur Page 16