Greetings
i used interface Vumat with Umat for simulating CEL problem, after 50% of analysis, i got the error as “Excessive incremental rotation of the elements in element set ” i researched the meaning about this error in literature but h couldn’t find how fix it. Anybody can help me and advise.
Regards
CEL analysis using hypo plasticity Vumat
Related Articles
-
Triaxial Callibration test with Hypoplasticity
pooyan ghasemi||Constitutive Modelling|3 |Views 4,015
Dear all I am trying to calibrate the HP for sand, and I have quite comprehensive data. but they are not totally consistent with each other . we have the […] -
Question on the Matlab driver – model hypo Sand
c sx||Constitutive Modelling|1 |Views 3,987
As a beginner to soil constitutive modelling, I am learning the hypoplastic models by reading the matlab drivers. I am confused with the matlab file f_hyp.m in the model hypo_sand. […] -
Hypoplastic sand-mr parameter calibration
anis kheffache||Constitutive Modelling|2 |Views 4,103
Dear all, I have a question about Hypoplasticity for sand model, i am having trouble to understand about how to calibrate the mr parameter ? Since no formula is provided […] -
Degradation ( disturbance ) of hypoplastic clay
jh xue||Constitutive Modelling|0 |Views 60
Hello everyone, I want to use ABAQUS to do the degradation of hypoplastic clay, but you can ‘t do it with umat. Changing K, A, sf in ABAQUS has no […] -
Hypoplasticity & Recent Stress History
Hashmi Sohawon||Constitutive Modelling|2 |Views 4,252
Hi David, Can you please provide some comments on the ability of the Hypoplasticity model with intergranular strain concept to model the effects of recent stress history on the clay […] -
Multi-objective analysis of the Sand Hypoplasticity model calibration
Francisco Mendez||Constitutive Modelling|0 |Views 952
I am happy to announce that our pre-print paper, “Multi-objective analysis of the Sand Hypoplasticity model calibration”, is available on researchgate (https://www.researchgate.net/publication/369199567_Multi-objective_analysis_of_the_Sand_Hypoplasticity_model_calibration) and Axive (https://doi.org/10.48550/arXiv.2303.07234). In this work, we study […] -
Mohr Coulomb umat in Abaqus
Shuhan Cao||Constitutive Modelling|4 |Views 5,233
Dear all, does anyone have the umat code for Mohr Coulomb in Abaqus? For my current work I need a umat for Mohr Coulomb in Abaqus. It would be highly […] -
SSE and SPD Mohr Coulomb Crieria
Matías Sáez de Tejada||Constitutive Modelling|1 |Views 4,596
I have a UMAT of Mohr Coulomb with no hardening, where i have to define SSE (specific strain energy) and SPD (specific plastic dissipation). Any idea?
Who is Online
No one is online right now
Search SoilModels Website
Recent posts
- Degradation ( disturbance ) of hypoplastic clay 23.4.2024
- Degradation ( disturbance ) of hypoplastic clay 23.4.2024
- Paper of Coulomb, C. A. (1773) 15.4.2024
- ABAQUS UMAT of hypoplastic clay model 6.4.2024
- Prague Geotechnical Days 2024 “Geotechnical monitoring” and 30th jubilee Prague Geotechnical Lecture by prof. Eduardo Alonso 5.4.2024
- UMAT for Creep-SCLAY model. 1.3.2024
- Cyclic tests with Triax element test driver 14.2.2024
- SUMMER SCHOOL ‘Numerical Modelling in Geotechnical Engineering’, Innsbruck – July 22nd-26th, 2024 1.2.2024
- COURSE IN SOIL MODELING – NTNU, Trondheim – October 14th to 18th, 2024 21.12.2023
- MSE walls design in Plaxis 11.12.2023
- sand liquefaction modelling in Anura3D 8.12.2023
- BCV bentonite experimental and modelling datasets 14.11.2023
Recent Comments
- Jh Xue on UMAT Implementation in Abaqus (Hypoplastic clay Subroutines)
- Santosh Katuwal on PM4Sand for Plaxis Download
- KHA DIDJA on SANISAND Abaqus UMAT and Plaxis implementations
- Debdip Das on SANISAND Abaqus UMAT and Plaxis implementations
- Ramon Varghese on SANISAND for FLAC3D Download
- Akhtyar Gul Shirzoi on ABAQUS UMAT of hypoplastic clay model
- KHA DIDJA on Animating Soil Models
- Jh Xue on Undrained Tests with Clay Hypoplasticity Intergranular
- Zhentao Liu on Problem in simulating CPT using SANISAND04
- Gertraud Medicus on ABAQUS UMAT of hypoplastic clay model
- Chen Zhiming on Download Package of Charles University Implementation of High Cycle Accumulation Model
- Konstantinos Chatzis on Cyclic tests with Triax element test driver
- Abhay Pratap Singh on Cyclic tests with Triax element test driver
- Giovanni Ciardi on Cyclic tests with Triax element test driver
- Konstantinos Chatzis on Cyclic tests with Triax element test driver
- Ismail Khan on Cyclic tests with Triax element test driver
- Kanika Lamba on Cyclic tests with Triax element test driver
- Arie Koot on How to model the settlement in soil due to water drawdown.
Hello Elfattah,
most probably your time step is too large. You can arbitrary decrease it with the “time scale factor” (maybe other name) in the “Step” module.
I recommend you should familiarize yourself with the theory of the CEL method. This might help you to solve the problem related to these error messages related to the CEL method in ABAQUS.
Best regards
Johannes
Dear Labenski
thank you for response, CEL depend on fixing the the mesh in space, so the distortion shall not be developed. i tried to reduce the time and mesh size, but the error is displayed after about 25 % instead of 50 % of analysis. Noted I used interface Vumat/Umat by Britta Bienen
Actually the mesh is not fixed as you might expect. The CEL method consists of three steps. In one step, the “fixed” mesh will be deformed according to the load and the corresponding material response. In a latter phase the deformed mesh will be resetted to its initial position, i.e. as user you think the mesh is fixed in space.
So reducing the time step with the time scaling factor (see image: https://imgur.com/a/kEHLYRy) usually worked for me to resolve this problem with CEL simulations. By standard I use a time scale factor of 0.9, but sometimes you may need even smaller factors. Of course, the computational time is increasing if you decrease this factor.
I see, i have already tried to use time scale factor to 0.5 and 0.85, but the error is displayed after about 25 % instead of 50 % of analysis. in addition, i tried too reduce the mesh size but i still receive the error. this error appear when i use Vumat. in contrast, the analysis has complete using anther constitutive law such as Mohr Coulomb or cap plasticity with the same model.
Did you receive this error before for CEL model ? and do you think that there problem in Vumat/Umat interface ?
I am using the Vumat-Umat interface for vibratory-pile installation simulations without problems. In most cases I could resolve this error with the time scale factor. You should also check if your boundary conditions are defined correct. You should only define boundary conditions you really need. Do not constrain all DOF at all boundaries, if you don’t need to.
the error element is existing at symmetry face near the contact zone
in addition, the energy balance is not normal. because the dramatically decreasing of total energy is occurred and the internal energy is very low. Noted, there is message state the the stretch element instead of gradient deformation
Hello
subscribe to and seek assistance from the
ABAQUS mailing list
https://groups.yahoo.com/neo/groups/Abaqus/info
Search the archive of the list before posting in it.
The list does not accept attachments.
Or
http://www.eng-tips.com/threadminder.cfm?pid=799
or from the ResearchGate discussion forum.
For advice on mechanics in general, including modeling,
you can consult
http://imechanica.org/
If you need subroutines: as an introduction get the file
http://imechanica.org/files/Writing User Subroutines with ABAQUS.pdf
Good luck
Frank