After several decades of development we are happy to announce that the Tochnog Professional finite element program has become free. Both for academic and commercial use. We are extremely grateful […]
Dear all Is the basic Hypo-Plastic model (Wollffersdorff’s model) suitable for 3D models? Can I analyze 3D models with this UMAT? (https://soilmodels.com/download/umat-hyposand-uibk/) Thank you Sobhan
Modified Cam clay model now supported in automatic calibration software ExCalibre
||Constitutive Modelling|6 |
Free SoilModels automatic calibration software ExCalibre, available at, https://soilmodels.com/excalibre/, now supports Modified Cam clay model. This is both for laboratory test simulation as well as for automatic calibration. We hope […]
Hi David, I have reproduced some single elements test on ABAQUS using the UMAT to compare with Triax Hypoplasticity. So far, my stiffness curve (q vs ea) and my stress […]
Where the client was forced to make all his horizontal loaded Dolphins (piles) 10 m longer we could trustworthy proof that this actually was not necessary saving millions of cost […]
Hi all, I wanted to ask if anyone has experienced this error before when running the Hypoplastic UMAT (umat_hcea.for) on Abaqus? “Abaqus Error: The executable standard.exe aborted with system error […]
On the simulation of the cyclic mobility effect with an ISA -hypoplastic hypoplastic hypoplastic model, is it possible to simulate 3D liquefiable sandy soil by available u-mat file which is […]
Is the Sanisand constitutive model 3 dimensional? Could it be used for dry sand cases using C4D8 elements? (drained sand) Is it possible to apply it in a dynamic implicit […]
Hi David, I am trying to reproduce some Triaxial data from Coop et al. (1995) using the Hypoplastic Model with Intergranular Strain Concept on Triax. So far, I cannot get […]
Dear all, I recently conducted a numerical simulation of pile-soil interaction. I digged a vertical hole and insert the pile into that with general contact. Due to many reasons, I […]
I am trying to calibrate my sand using Excalibre. I tried some triaxial element tests using Abaqus. However the results are different between Excalibre and Abaqus.
Dear all, I’m trying to model multilayer soil in abaqus. To use the SaniSand umat in model I use the following parameters but no plastic strain at all. The unit […]
I tried to model sample of triaxial test in Abaqus program. I used hypoplastic subroutine. The parameters used in hypoplastic model was Hochstetten sand the given in website “https://web.natur.cuni.cz/uhigug/masin/plaxumat/node5.html”. The […]
Dear all, The sand hypoplastic model has been used to simulate the interaction between soil and pile. However, there is a bad convergence in the process of calculation. When I […]
Dear community I have 4 Question in implementation of Hypo-sand Umat in ABAQUS could someone kindly explain? 1. I checked the Umat file from (https://soilmodels.com/download/plaxis-umat-hypoplas-zip/) and i understand this subroutine […]
Dear all, When I check the umat file of sand hypoplastic modeling, I find there are two parametesr(p_t(2), bulk_w(15)) without any definitions. Could someone kindly explain the exact meaning for […]
Dear all I’m studying hypo-plastic constitutive law from beginning concepts I traced concepts successfully until i faced **rate independent topic** i read this topic in the prof. Wolfgangs paper (hypo-plasticity […]
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_camclay. […]
hi every one i’m using abaqus 2017 and i want to implement Hypo-sand to my Biaxial model (2D) and before all, i linked abaqus and fortran successfully my question is […]
hi, every one i have problem with fortran format my abaqus is 6.14 and this version accept (.for) format for fortran but some subroutines are in (.f ) format is […]
Good evening, everyone. I find it difficult to apply equations (13) and (14) of Herle’s publication “Determination of parameters of a hypoplastic constitutive model from properties of grain assemblies”. As […]
Dear SoilModels community Dear Prof. Masin / all I want to know how HP model considers Ko variation for the following cases: Ko with variation with OCR? Ko determination related […]
Hi everyone I am writing a code for a model in the UDSM format for Plaxis. I already have the “*.dll” files, but when I run the soil test I […]
Hi all, I wanted to share these results to show that the use of the hypo clay model does in fact give more realistic undrained stress paths for clays on […]
Dear Prof David / SOil model community, I am performing coupled consolidation analysis for deep excavation in clay using HP clay model in Plaxis 3D. Performing the undrained analysis, the […]
Hi Prof. David, I have obtained these results in that attached picture using Triax and got confused when seeing that an isotopically normally consolidated sample does not follow a trend […]
Dear PhD, I am studying roller vibrations on sandy soil models with vumat. Can PhD give me the subroutine model and input parameters of objects for reference? Unit of the […]
Hi all, After successfully testing a linear elastic Umat on Abaqus, I am now trying to test the Hypoplastic model Umat. I intend to carry out a drained triaxial single […]
Dear Community, I want to include a non-local regularization technique in the built-in Mohr-Coulomb model of abaqus to capture the strain-localization effects. I am trying to find the original VUMAT […]
Hi everyone When I use sanisand model in abaqus , This error is seen Can anyone help? Other subroutines work well for me Is it possible for my input parameters […]
hello every one i have a problem with abaqus subroutine can i use hypoplastic umat file that prepared for palxis in this website in abaqus? or the files must be […]
Hello everyone, I have just a general question how people approach the problem of spurious oscillations generated in dynamic analysis when using nonlinear soil constitutive models. I understand sometimes numerical […]
I am using the mesh-to-mesh solution mapping with MCC model. The element type used is CPE8RP. My initial analysis runs without any issue and when the deformations reach a certain […]
Hello all, i did the automatic calibration for the Dobrany and Motol sand and tried to model the soil tests also in Plaxis and then to compare both. For the […]
Dear community, I’m interested in constitutive models that can handle strain-rate effects for HSR on sands for simulating free fall penetration. I would appreciate any help. Do you know any […]
Dr. Masin I have downloaded the most recent dll for Plaxis that includes the HypoPlastic model for Clays that you developed. I see two new parameters (Gvh0 and n), both […]
if you could please let me know whether Is there any constitutive model exist for capturing cyclic response for cemented materials just like cemented sand and gravelly soils.
Hi everyone, I work on soil constitutive models and I want to compare soil behaviours with various constitutive models but I can’t find Lade umat in the .for format. Can […]
Hello all, i have another question regarding the calibration process. Why do the initial void ratios differ between the input file and the output from excalibre? What is done during […]
Dear All, I am using sand hypoplastic model in my research and I have encountered some problem when looking into cyclic simple shear test in the range of small strains. […]
Dear Prof. David Mašín Greetings I would like to discuss with you an issue. I have a problem in my simulation on ABAQUS. The problem in the simulation results is […]
Hello all, According to my last post some weeks ago I now have translated the laboratory data from engineering strain to true strain with the following formula: epsilon(true)=ln(1+epsilon(engineering)). I compared […]
Greeting Everyone, I’m a new user of ABAQUS. I’m trying to simulate soil dynamic compaction by Cap model. I simulated the blow by half sinusoidal wave. Although I used Cap […]
Dear all, I’m facing trouble in calculating NO. 16 parameter in the UMAT for sand hypoplasticity by Dr. Masin, any help will be really appreciated especially with an example. Best […]
Hello, everyone I am an abaqus user and developer. Recently, I want to simulating the liquefaction phenomenon with abaqus/standard or abaqus/explicit. As I know, this cannot be realized using the […]
Hi all, Can somebody recommmend a good detailed guide for the procedures required to link ABAQUS 6.14 to Intel Fortran Compiler and Microsoft Visual Studio? Thank you, Hashmi
Are the slides in regards to Stiffness Anisotropy for Clay Hypoplasticity for the PhD course available online? The available document {Mašín, D. (2015) Part 4: Determination of material parameters, PhD […]
Hello all, i hava a problem with the Oedometer curves after the automatic calibration with ExCalibre. I took the Dobrany sand dataset for an automatic calibration and then i copied […]
Which software has the feature to model soil settlement due water drawdown?
Dear all I am using the UMAT of hypoplastic model for simulation soil (3D modeling) under cyclic loading. The analysis was completed at geostatic step. But for consolidation step (soil, […]
Supporting Organisations
Recent posts
-
Problem in “Hoek Brown Softening” Model 30.4.2026
-
XFEM Hydraulic Fracturing in Abaqus – Pore Pressure Not Updating & Extremely Small Time Steps 28.4.2026
-
Correct my Plaxis FEM simulation in foundation bearing capacity results 3.4.2026
-
mohr coulomb 2D yield surface vs 3D mohr coulomb yield surface 28.2.2026
-
Problem with GeoStudio (Seepage) software 16.2.2026
-
Prague Geotechnical Days 2026 3.2.2026
-
Postdoctoral position at COFS, UWA 28.7.2025
-
Hypoplasticity clay in ABAQUS 23.7.2025
-
Drucker-Prager Cap 29.5.2025
-
Abaqus RITSS with hypoplastic 9.4.2025
-
Fellin UMAT subroutine 2.4.2025
-
Hypoplasticity clay for triaxial compression in abaqus 26.3.2025
Recent Comments