Hello guys Could you help me, please
I have 02 questions:
1) How do you get the full signal from the load applied over 1 second, knowing that it depends on the frequency each time you change it?
2) Does the load signal given by Plaxis allow me to give it a FFT?
Bekakra Sofiane
Hi Sofiane,
1. When defining a harmonic function for your displacement or load multiplier in the Multipliers window, the preview window will always show you a signal with two complete cycles. Theoretically, the signal continues to infinity. Still, that is not relevant to your analysis as your calculation will consider only the duration of the dynamic time interval you define for your Phase.
2. Suppose your input signal is an accelerogram (Table signal > Accelerations type). In that case, it can be visualised in different representative charts: Fourier spectra, Response spectra and Arias intensity (see Chapter 7.5.6 of the PLAXIS 3D - Reference manual). Conversely, when plotting curves in dynamic calculations, it is possible to automatically transform the generated curves from the time domain to the frequency domain using the Fast Fourier Transform (FFT) (see Chapter 10.2.5 of PLAXIS 3D - Reference manual).
Hi sir, I completely agree with you, but the problem is that I am calculating the displacements for a time interval of 1 second or (x second=dynamic time interval) and I am obliged to calculate the load dynamic for 1 second (x second=dynamic time interval) to make the division, I have to look for the impedance functions of the foundations.
Dear Sofiane,
I'm not following your question. If you specify in PLAXIS a Dynamics time interval of 1 second, you will calculate the dynamic load for 1 second. Why does that not solve your problem?
With kind regards,
Dennis Waterman
Dear Desnnis ,
How do you calculate the dynamic load for 1 second knowing that the frequency is changed?
Sofiane Bekakra
I still don't understand your question "how do you calculate the dynamic load". What do you want to calculate then? In a dynamics analysis one applies a dynamic load... And what does frequency change have to do with that? You really have to come with a clearer description with what you exactly want to do.