# Spectral Response Acceleration Parameters.

**Dimensional *** map spectral acceleration coefficient* , four different

*for*

**levels of earthquake ground motion***Earthquake Hazard Maps*are defined under:

*Map spectral acceleration coefficients S *_{S} and *S *_{1} , **spectral acceleration coefficients S **** _{DS}** and

**S****'is converted to automatically:**

_{D1}**Symbols**

* F_{S }= *Local ground impact coefficient for the short-period region

*Local ground impact coefficient for a period of 1.0 seconds*

**F**_{1 }=*Short-period design spectral acceleration coefficient [dimensionless]*

**S**_{DS }=*Design spectral acceleration coefficient for a period of 1.0 seconds [dimensionless]*

**S**_{D1 }=*Short period map spectral acceleration coefficient [dimensionless]*

**S**_{S }=*Map spectral acceleration coefficient for a period of 1.0 seconds [dimensionless]*

**S**_{1}=**Dimensional *** map spectral acceleration coefficient* , four different

*for*

**levels of earthquake ground motion***Earthquake Hazard Maps*are defined under:

**(a) **Short period *map spectral acceleration coefficient S *

_{S}**(b) ***Map* spectral acceleration coefficient **S **** _{1}** for a period of 1.0 seconds

The * map spectral acceleration coefficients* corresponding to the geometric mean of the earthquake effects in two horizontal directions perpendicular to each other are determined by the

*map spectral accelerations*for 5% damping rate based on the reference ground condition for a given earthquake ground motion level [(

*V*

_{S 30}) = 760 m / s] . They are defined as

*divided by the acceleration of gravity . For this reason, the equation described below is used to determine the effect of local soil impact coefficients while calculating under different soil conditions.*

**dimensionless coefficients***The map spectral acceleration coefficients S *_{S} and *S *_{1 }* are* converted into the

*design*

**spectral acceleration coefficients S****and**

_{DS}

**S****as follows :**

_{D1}Wherein *F *_{S} and *F *_{1} are defined below **the local ground effect coefficients**** of the** shows.

In the Analysis Settings Wizard - Design Spectrums tab, design acceleration coefficients are obtained with the map spectral acceleration coefficients obtained depending on the coordinate with online and offline options. If the online option is used, acceleration coefficients are obtained from the *AFAD Earthquake Hazard Map*. The acceleration coefficients calculated over the program infrastructure are obtained in the offline option. Both options give the same results.

**Next Topic**