Code spectra and site specific spectra

Code Spectra

Different analysis procedures are provided for determining the elastic design response spectrum, the first of which is simply to adopt the code spectra appropriate to the Seismic Loading action code selected for the model.

Default spectra

Site Specific Spectra (user defined)

In addition to the code spectra, Tekla Structural Designer also allows you to define your own site specific spectra by specifying significant periods and acceleration. This procedure is applicable to both ELF and RSA analysis.

The curve equations used for the different Seismic Loading action codes are as follows:

Site Specific Spectra (user defined - generic curve)

A third route is to set a site specific generic curve, either manually, or by pasting data from a spreadsheet. This procedure requires an RSA to be run (not ELF). This has been added primarily for remote markets using the following US Seismic Loading action codes:

ASCE 7-05
ASCE 7-10
ASCE 7-16

It is not available for UBC, EC or IS codes as these codes do not define the process to be used with a generic spectrum.