ANSYS is a finite element package developed by ANSYS, Inc. This analytical software have been used to simulate a variety of complex problems in civil, geotechnical and earthquake engineering.

The UCSD soil models UCSDSAND3BETA and UCSDCLAY have been integrated into ANSYS as user defined material models. These material models are capable of simulating the essential characteristics of sands and clays respectively. Additional references can be found here.

Example of 1D site response analysis which utilizes the demo versions of the soil models is provided below (for illustration purposes). For the 3D full version of the soil models, please contact Prof. Ahmed Elgamal (E-mail: elgamal AT ucsd DOT edu).

1D Seismic Site Response Example

Please follow the steps below to download, install, and run the ANSYS_Example. For additional information, please reference the user manual.

Step 1: Download and Installation

    1) If you do not have ANSYS installed, please visit to obtain the analysis package.

    2) Download ANSYS_Example.rar (10 MB, updated Coming Soon!)

    3) Unzip all files in the ANSYS_Example.rar to a desired location. The zip file includes the material models (USERMATLib.dll), and an excel sheet interface (1D_Seismic_Site_Response_Example.xlsm).

    4) Please move USERMATLib.dll (contained in the above Example file) to the winx64 folder in the bin folder. (ex. "C:\Program Files\ANSYS Student\v181\ansys\bin\winx64"). If the path was changed, please move to the appropriate folder.

    5) Update ANSYS_location.txt with the location of the ANSYS installation.

Step 2: Run 1D_Seismic_Site_Response_Example

    1) Open 1D_Seismic_Site_Response_Example.xlsm. If prompted please enable macros. This Excel sheet makes use of macros to generate input files for ANSYS and run the analysis.

    2) Update the material and analysis parameters shown on the Excel sheet and then click "Create Input and Run" to start the analysis in ANSYS.

    3) Upon completion of the analysis click "View Results" to load the output.

Model Performance

Below are some sample responses using UCSDSAND3BETA for seismic analysis. Click images to see full sized versions.

Soil Model in ANSYS
Shear Stress Contour


For information on how to use the soil models UCSDSAND3BETA and UCSDCLAY in ANSYS, please click here.