Users Forum
ADONIS Category => Bugs and Problems => Topic started by: Jay Gawai on March 05, 2025, 03:06:37 am
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I have developed two geotechnical models in Adonis without any supporting system, ensuring that all properties have been assigned as per the tutorials. The models were analyzed up to the excavation stage with 9.8 m/s? gravity applied, but both exhibit excessive displacement values.
1. First Model (Elastic Model) (Without Any Supporting System):
Process: Created geometry, generated mesh, assigned soil properties, applied boundary conditions, excavated the model, applied 9.8 m/s? gravity, and run the model.
Dimensions: 30 m horizontal, 18 m vertical, and 10 m excavation depth.
Results: X-displacement: 14,500 meters, Y-displacement: 25,000 meters.
2. Second Model (Plastic Hardening Model) (Without Any Supporting System):
Process: Created geometry, refined mesh (edge size up 1.5), assigned initial soil properties, applied boundary conditions, excavated the model, applied 9.8 m/s? gravity, and run the model.
Dimensions: 120 m horizontal, 100 m vertical, and 32 m excavation depth.
Results: X-displacement: -11,500 meters (-1.15E+04), Y-displacement: -11,300 meters (-1.13E+04).
Given that all input parameters follow the tutorial guidelines, what could be the potential reasons for these excessive displacement values?
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Hi,
Make sure to save the model in the *.ajs format, which indicates the script file. After that, open the script, clean it up, and attach it here so I can recreate the issue.
Note that a similar example of the script is included at the end of each tutorial in case you're not familiar with it.
-Roozbeh
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"Thank You for Your Reply ? Excessive Displacement Issue in ADONIS (AJS Files Attached)"https://drive.google.com/file/d/1TbevTdcBPjXLN96IoRhcCPV-Na5tp6PO/view?usp=sharing (https://drive.google.com/file/d/1TbevTdcBPjXLN96IoRhcCPV-Na5tp6PO/view?usp=sharing)
https://drive.google.com/file/d/1xIoKyQcqdlIL4tCJSIkWPV2SpJ5gT4Ua/view?usp=sharing (https://drive.google.com/file/d/1xIoKyQcqdlIL4tCJSIkWPV2SpJ5gT4Ua/view?usp=sharing)
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Hi
I see that you assigned the Mohr-Coulomb constitutive model to the ground and excavated a trench without any support. Naturally, the excavation is failing due to the lack of reinforcement.
It looks like you're new to numerical modeling. I recommend first studying constitutive models and soil mechanics before diving into simulations. Understanding soil behavior is essential before getting into detailed modeling. Let me know if you need any guidance!
-Roozbeh
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Hi,
I understand that the excavation is unstable without support. My intention was to analyze displacement behavior under different conditions?without support, with sheet piles, and with sheet piles and anchors?for comparison. The results show X-displacement of 14,500 meters and Y-displacement of 25,000 meters, indicating excessive deformation.
I am very curious to observe displacement up to the excavation stage without any retention system, as well as the displacement behavior with retention systems such as sheet piles, diaphragm walls, or anchors. If I want to excavate to this extent and observe how much displacement occurs without any retention system, is it possible to achieve this within the software?
Best regards.
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I understand, but large displacement indicates failure. ADONIS operates on a quasi-static explicit FEM, meaning the model will continue running until manually stopped. Since small strain is the default, the mesh does not update, allowing the simulation to proceed despite large displacements. It is your responsibility to stop the model.
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Dear Dr. Roozbeh,
I hope you are doing well. I am conducting a deep excavation analysis using ADONIS and employing the Plastic Hardening Soil Model for geotechnical simulation.
Model Details:
Excavation Dimensions: 120 m horizontal length, 100 m vertical depth (large-scale excavation simulation).
Support System: 32 m diaphragm wall for excavation support.
Ground Anchors:
Anchor 1: 19.8 m total length, 8 m anchor bonding.
Anchor 2: 23.3 m total length, 8 m anchor bonding.
Anchor 3: 23.8 m total length, 8 m anchor bonding.
Displacement Results:
1. Three anchors ? X displacement: 22.7 mm
2. Two anchors ? X displacement: 17.7 mm
3. Three anchors (re-evaluated) ? X displacement: 12.8 mm
Logically, reducing the number of anchors should increase displacement, but my results show an inverse trend. I have carefully reviewed boundary conditions, anchor properties, soil parameters, and meshing, yet the discrepancy persists.
I have also sent you the AJS files of my three models for your reference. You can access them via the links below:
Model 1 (Three anchors): https://drive.google.com/file/d/1ENMlOWrfjcw5P-5fLNsgm41MS3YDlYY_/view?usp=sharing (https://drive.google.com/file/d/1ENMlOWrfjcw5P-5fLNsgm41MS3YDlYY_/view?usp=sharing)
Model 2 (Two anchors): https://drive.google.com/file/d/1nMTLga7Zgx-rEYoYNm9fOx9MT02kY34x/view?usp=sharing (https://drive.google.com/file/d/1nMTLga7Zgx-rEYoYNm9fOx9MT02kY34x/view?usp=sharing)
Model 3 (Three anchors ): https://drive.google.com/file/d/14-boQyI58deDHg9vZAn7fOafQ0BzqwQB/view?usp=sharing (https://drive.google.com/file/d/14-boQyI58deDHg9vZAn7fOafQ0BzqwQB/view?usp=sharing)
What could be the problem?
I didn't able to guessed the displacement shown in plot and its value. Whether value shown in maximum value?
If I plot query counter Y axis and X axis notations are not clear for X or Y displacement.
If possible kindly send ajs file used by you for solving to understand in Tutorial.
I appreciate your time and guidance and look forward to your response
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Your model is overly complex. Please use a simpler model while keeping the constitutive model unchanged. Then, use this simplified model as a foundation for adding and removing the tiebacks. This approach will ensure clarity and allow for easier comparison.