What Is EZ-FRISK™?
What Can It Do for You?
Technical Capabilities
Purchasing EZ-FRISK™
Register Now!

Learn More About Working With Seismic Hazard Analysis

EZ-FRISK™ Technical Capabilities

Attenuation Equation Database

EZ-FRISK™ contains a large number of programmed attenuation equations along with their coefficients. The following standard equations are included:

EZ-FRISK™ provides and supports attenuation equations that calculate:

The standard attenuation equation database includes variants for many modern attenuation equations that use the FEMA P-750/2009 Edition NEHRP Recommended Seismic Provisions method for calculating the maximum rotated component of ground motions. This helps user meet the requirements of:

The attenuation equation database can be used with any number of seismic hazard analyses. You can select one or more attenuation equations to use with each seismic source. You can also assign different equations to different sources. You can assign custom weights to each attenuation equation used with a source. For example, you can assign different attenuation equations to subduction zones then those used for your fault or gridded seismic sources. You can easily recalculate results if the attenuation equation database is updated.

EZ-FRISK™ allows you to define your own custom attenuation equations, to implement newly published or proprietary ground motion prediction equations. You can copy and modify existing standard equations, or create completely new equations using an expression evaluator. When you use the expression evaluator, you specify the predicted mean ground motion, as well as the log-normal standard deviation using a simple formula syntax. These formulas can depend on any rupture metric calcuated by EZ-FRISK. You can specify custom site parameters, as well as spectral-period and faulting-mechanism dependent coefficients.