Open topic with navigation

Response spectrum generator according to IS (Indian standard)

Procedure to input a new IS (Indian Standard) seismic spectrum

1. Expand branch Libraries of the main tree menu.
2. Expand sub-branch Loads.
3. Start function Seismic spectrum to open the Seismic Spectrum Manager.
4. Click button New.
5. In combo box Input type select option Indian Standard.
6. Review and, if required, adjust the spectrum parameters.
7. Click button Code parameter to review or modify the code-defined parameters of the spectrum.
8. Confirm the code parameters with OK.
9. Click OK to confirm the spectrum.
10. Close the Seismic Spectrum Manager.

Spectrum definition and code parameters

A response spectrum can be defined according to IS by selecting Indian standard as Input type.

Max frequency & Step

The values of the spectrum are generated between a maximum period of 4 seconds (=0.25 Hz) and the input maximum frequency, using the input Step value.

Code parameters

This button opens the dialogue defining the code-dependent parameters.

Zone

Seismic zone (II - Low, III - Moderate, IV - Severe, V - Very severe, User input)

Z

Zone factor - tabulated according to the selected zone or defined manually (user input)

I

Importance factor

R

Response reduction factor

Type of soil

Rock or hard soil, Medium soil, Soft soil

Damping percent

Relative damping ratio, given in %

Multiplying factor for Ah

F_u

I/R

Ratio I/R

Multiplying factor for damping percent

Calculated correction factor for damping

Theoretical background

Spectral acceleration coefficient:

Limitation of the Importance factor and Response reduction ratio:

Acceleration for the specified period T:

Open topic with navigation