# Horizontal Elastic Design Spectrum.

**Symbols**

**F _{S} = **Local ground effect coefficient for short period region

**F**Local ground effect coefficient for 1.0 second period

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

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

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

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

_{1}=**T =**Natural vibration period [s]

**T**Horizontal elastic design acceleration spectrum corner period [s]

_{A}=**T**Horizontal elastic design acceleration spectrum corner period [s]

_{B}=**T**Transition period to the constant displacement region in the horizontal elastic design spectrum [s]

_{L}=**S**Horizontal elastic design spectral acceleration [g]

_{ae}(T ) =The map spectral acceleration coefficients S

_{s }and S_{1 }values of the coordinates, specified at Building Geometry and Location, were obtained from the AFAD earthquake map data using the Analysis Wizard online option.According to the ZA local soil class specified in the geotechnical report,

*local soil effect coefficients are*obtained from TBDY 2018 Table 2.1 and the*Design spectral acceleration coefficients*are**automatically**calculated by the program.

S | 0.706 |

S | 0.205 |

F | 0.8 |

F | 0.8 |

S | |

S | |

T | |

T |

The horizontal elastic design spectral accelerations S

_{ae}(T), which are the ordinates of the horizontal elastic design acceleration spectrum for any earthquake ground motion level considered, are defined in terms of gravitational acceleration [g] depending on the natural vibration period.Based on the coordinates, the spectral acceleration coefficients obtained from AFAD and the horizontal elastic design spectrum S

_{ae}(T) are determined according to the formula below. For the horizontal elastic design spectrum, it is represented by a total of 4 functions, different in each region, is shown in the graph below.

In order to create the spectrum, the time should be increased with appropriate intervals starting from 0 seconds and stopped at an appropriate T value after T

_{L}=6 s. For this building, the horizontal elastic spectrum starting from T=0 s to T=8 s with 0.05 intervals is calculated in the excel. The obtained spectrum is given in the image below.