Deconvolution via Frequency Domain Analysis

The Deconvolution approach is the same as the frequency-domain equivalent linear analysis approach except that the input motion can be applied at the ground surface or anywhere else in the soil column. The corresponding rock motion is then computed and provided to the user.

Deconvolution requires the definition of a soil profile. The following properties need to be defined for each layer:

• Thickness
• Unit Weight
• Shear Wave Velocity (𝑉𝑠) or Initial Shear Modulus (𝐺𝑚𝑎𝑥)
• Damping Ratio (%)

To perform the deconvolution:

1. Open or create a new project.
2. In the Project Setup tab, select a Frequency domain profile (Linear or Equivalent Linear Analysis).
3. Select the Properties tab.
4. Define your Layer properties for the layer(s) of the soil column (ensuring the ones listed above are included).
   
5. Select the Bedrock (bottom) layer, and enter the Layer properties for the Bedrock layer.
6. Tick the checkbox labeled Deconvolution.
7. Use the Motion recorded at top of layer drop down to specify the point of application of the ground motion.
   
8. Use the Output motion for selected layers drop down list to select the type of ground motions to be generated as output (either Within or Equivalent Outcrop).
9. In the Motions tab, select the motion(s) to be deconvolved.
10. In the Compute tab, enter the Frequency domain parameters.
11. Next to Bedrock, tick the checkbox for Output deconvolution result at top of rock.
12. Click Compute.

The output from a deconvolution analysis is a set of RSSeismic formatted motions. Additional files will be produced for each layer output requested and will be located in the [Project name]\Motion[Name] folder. These .txt files can be used directly in RSSeismic.