Response spectrum generator according to DIN (German standard)

Procedure to input a new DIN 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 DIN - German 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 DIN by selecting DIN - German 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.

S, Tb, Tc, Td manually?

When this option is No, S, Tb, Tc, Td are obtained a table, depending on the selected subsoil type

When this option is Yes, S, Tb, Tc, Td are defined manually

Horizontal / Vertical

Direction of the seismic action: horizontal or vertical

Subsoil type

Category of subsoil (A-R, B-R, C-R, B-T, C-T, C-S)

S

Subsoil factor, obtained from table or defined manually

Tb

Lower limit of the period of the constant spectral acceleration branch, obtained from table or defined manually

Tc

Upper limit of the period of the constant spectral acceleration branch, obtained from table or defined manually

Td

Value defining the beginning of the constant displacement response range of the spectrum, obtained from table or defined manually

coeff. accel. ag

Value of the nominal acceleration expressed as a multiple of the acceleration of gravity g

ag - nominal acc.

Nominal ground acceleration

Beta0

Magnification factor for the acceleration spectra

Gamma

Importance factor

q factor - manual input / more parameters

When this option is set as manual input, the value of q is defined manually

When this option is set as more parameters, the value of q is calculated

q

Behaviour factor

Structure type

Type of shear-resisting system

- Frame, wall system, mixed system (3.0)

- Core system (2.0)

- Reverse pendulum system (1.7)

Regularity

Regularity of the shear resisting system

- regular systems (1.0)

- non-regular systems (0.8)

Kw factor

Correction factor for the calculation of q

 

Theoretical background

Design response spectrum

The seismic response spectrum is defined as

The tabulated values of S, Tb, Tc, Td for the horizontal spectrum are defined as

Subsoil type S [-] TB [s] TC [s] TD [s]
A-R 1.00 0.05 0.20 2.0
B-R 1.25 0.05 0.25 2.0
C-R 1.50 0.05 0.30 2.0
B-T 1.00 0.10 0.30 2.0
C-T 1.25 0.10 0.40 2.0
C-S 0.75 0.10 0.50 2.0

For vertical spectrum, use the values defined above, modified as follows:

TC = 0.20 s

Behaviour factor

When requested, the behaviour factor is calculated as

Structure type q0
Frame, wall system, mixed system 3.0
Core system 2.0
Reverse pendulum system 1.7
Regularity Kr
Regular systems 1.0
Non-regular systems 0.8

Kw is defined by the user.