FAQ 000243 EN-US 12/01/2017

Robert Vogl Calculation

How do I choose the time step for the time history analysis (using the implicit Newmark solver)?

Answer

The selection of the time step depends on the natural frequency f of the system or the frequency of the exciting forces. To achieve a sufficient precision, the governing period T = 1/f is divided in about 20 steps, that is, the time step Δt is to be selected as follows: Δt <T/20 = 1/(20 f) = π / (10 ω)

For transient defined excitations, such as accelerograms or time course monitors in tables, the shortest time period should be divided in 7 steps: Δt = Min{ti+1 - ti} / 7

In RF-/DYNAM Pro, time steps can be automatically determined for the calculation. However, this is done by means of the defined accelerograms or time course monitors. Therefore, the manual entry of this time step should be considered. Regardless of the calculation, time steps are specified to save the results.

Keywords

time step time history analysis natural frequency accelerogram time course monitor

Contact us

Contact Dlubal Software

Did you find your question?
If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

(267) 702-2815

info-us@dlubal.com