Natural frequency, Mesh element size, Rayleigh damping, vertical force on retaining wall model

Q1: Is there any way to determine natural frequency of Retaining wall soil numerical model from PLAXIS?

 

Q2: How can we see the exact element mesh size in PLAXIS?

 

Q3: I am using Mohr-Coulomb soil model and want to introduce constant Rayleigh damping of 3%.

Natural frequency of soil is 16.53 Hz, frequency of input motion is 5.0 Hz

I used ξ= 3 % for both Target 1 and Target 2

f = 16.53 Hz for Target 1 and f = 5/16.53 = 1.0 (closest odd multiple integer) Hz Target 2

w, α, β are calculated automatically but when I close Material window and edit material, all Rayleigh damping parameters ξ , f, w, α, β are reset to different values. How can I solve this issue?

 

 

Q4: How can we plot total vertical wall force on the wall vs time graph in PLAXIS? (Rigid retaining wall) See Pdf file attached 

 

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