# UDEC **URL:** https://forum.itascainternational.com/c/udec/8.md [Latest](https://forum.itascainternational.com/latest.md) · [Categories](https://forum.itascainternational.com/categories.md) · [Tags](https://forum.itascainternational.com/tags.md) --- ## [About the UDEC category](https://forum.itascainternational.com/t/about-the-udec-category/15)
**Author:** [@jhazzard](https://forum.itascainternational.com/u/jhazzard)\ **Replies:** 1\ **Last updated:** [February 8, 2022, 3:11am UTC](https://forum.itascainternational.com/t/about-the-udec-category/15 "2022-02-08T03:11:59Z")
The Universal Distinct Element Code ( UDEC ) is a two-dimensional numerical program that simulates the quasi-static or dynamic response to loading of media containing multiple intersecting joint structures. The disconti… --- ## [Plot history for principal stress- maximum and minimum](https://forum.itascainternational.com/t/plot-history-for-principal-stress-maximum-and-minimum/1042)
**Author:** [@Binu](https://forum.itascainternational.com/u/Binu)\ **Replies:** 5\ **Last updated:** [November 7, 2025, 11:27am UTC](https://forum.itascainternational.com/t/plot-history-for-principal-stress-maximum-and-minimum/1042 "2025-11-07T11:27:16Z")
How to plot history for principal stress- maximum and minimum in udec. I tried Block zone history stress-p max 0,0 --- ## [Cannot apply Barton - Bandis model in latest UDEC version](https://forum.itascainternational.com/t/cannot-apply-barton-bandis-model-in-latest-udec-version/2248)
**Author:** [@MichaelK](https://forum.itascainternational.com/u/MichaelK)\ **Replies:** 5\ **Last updated:** [October 23, 2025, 12:21pm UTC](https://forum.itascainternational.com/t/cannot-apply-barton-bandis-model-in-latest-udec-version/2248 "2025-10-23T12:21:18Z")
Greetings, I am facing trouble on applying the Barton – Bandis model in UDEC 7 latest version (105). First of all I had trouble on assigning the B-B model in certain set of Joints. I would get the following message: “… --- ## [Thermal application in Voronoi UDEC Model](https://forum.itascainternational.com/t/thermal-application-in-voronoi-udec-model/2246)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 1\ **Last updated:** [October 8, 2025, 3:12pm UTC](https://forum.itascainternational.com/t/thermal-application-in-voronoi-udec-model/2246 "2025-10-08T15:12:11Z")
Hello all, I want to cool down the model from room temperature. But when I add voronoi and cool it down, the propagation doesn’t pass though the entire model, the change of temperature is only visible near the outer bou… --- ## [How to define the user-defined function in the C++ package of a new joint constitutive model as a pointer?](https://forum.itascainternational.com/t/how-to-define-the-user-defined-function-in-the-c-package-of-a-new-joint-constitutive-model-as-a-pointer/2132)
**Author:** [@jessie](https://forum.itascainternational.com/u/jessie)\ **Replies:** 4\ **Last updated:** [June 20, 2025, 4:33am UTC](https://forum.itascainternational.com/t/how-to-define-the-user-defined-function-in-the-c-package-of-a-new-joint-constitutive-model-as-a-pointer/2132 "2025-06-20T04:33:40Z")
--- ## [Material Property Number for Structural Elements](https://forum.itascainternational.com/t/material-property-number-for-structural-elements/2078)
**Author:** [@Jia](https://forum.itascainternational.com/u/Jia)\ **Replies:** 1\ **Last updated:** [May 15, 2025, 3:17pm UTC](https://forum.itascainternational.com/t/material-property-number-for-structural-elements/2078 "2025-05-15T15:17:20Z")
Hi all, just wondering if anyone know the material property corresponds to each number? The manual mentioned the property number ranges from 1 to 50, but I didn’t find any info in the manual for structural element like c… --- ## [Damping, mass scaling, timestep for bonded block rockslide runout](https://forum.itascainternational.com/t/damping-mass-scaling-timestep-for-bonded-block-rockslide-runout/2082)
**Author:** [@zack.tuckey](https://forum.itascainternational.com/u/zack.tuckey)\ **Replies:** 1\ **Last updated:** [May 14, 2025, 8:48am UTC](https://forum.itascainternational.com/t/damping-mass-scaling-timestep-for-bonded-block-rockslide-runout/2082 "2025-05-14T08:48:00Z")
Hi all, I’m playing around trying to create a trigon bonded block model of a step-path slope failure. The attached image shows my 200m high slope with 5m edge length trigon blocks. To be able to query stresses in the roc… --- ## [Apply interior boundary stress](https://forum.itascainternational.com/t/apply-interior-boundary-stress/2044)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 3\ **Last updated:** [April 22, 2025, 1:58am UTC](https://forum.itascainternational.com/t/apply-interior-boundary-stress/2044 "2025-04-22T01:58:57Z")
Hello everyone, I wanted to do a 2 step procedure on a model: Longitudanal confinement and release it Normal Wave Passing through the model The second step is easily achieved by applying a velocity/stress at outer bou… --- ## [Import CSV, write variables to contact extra slots](https://forum.itascainternational.com/t/import-csv-write-variables-to-contact-extra-slots/2048)
**Author:** [@zack.tuckey](https://forum.itascainternational.com/u/zack.tuckey)\ **Replies:** 1\ **Last updated:** [April 21, 2025, 3:24am UTC](https://forum.itascainternational.com/t/import-csv-write-variables-to-contact-extra-slots/2048 "2025-04-21T03:24:05Z")
Hi all, I am looking to create a plot that compares contact data from two different save states for different modelling scenarios in UDEC v7. From each of the two save states I have exported a text file with contact da… --- ## [Plot Maximum Unbalanced Force After Model Solved](https://forum.itascainternational.com/t/plot-maximum-unbalanced-force-after-model-solved/2017)
**Author:** [@Jia](https://forum.itascainternational.com/u/Jia)\ **Replies:** 5\ **Last updated:** [April 10, 2025, 4:54pm UTC](https://forum.itascainternational.com/t/plot-maximum-unbalanced-force-after-model-solved/2017 "2025-04-10T16:54:02Z")
Hi all, Is there any way to plot the maximum unbalanced force after the model has been solved? I didn’t write any command for recording an unbalanced force history before running the model. But I remember unbalanced for… --- ## [Change Properties in joints using ID](https://forum.itascainternational.com/t/change-properties-in-joints-using-id/2032)
**Author:** [@MichaelK](https://forum.itascainternational.com/u/MichaelK)\ **Replies:** 1\ **Last updated:** [April 8, 2025, 8:08am UTC](https://forum.itascainternational.com/t/change-properties-in-joints-using-id/2032 "2025-04-08T08:08:05Z")
Greetings to all, I would like help with the following (if possible..): Back in UDEC 6 when you built the model with the “crack” command you could set an ID to each crack. This way you could easily use these cracks wit… --- ## [Fish for the fragment in UDEC](https://forum.itascainternational.com/t/fish-for-the-fragment-in-udec/1067)
**Author:** [@xiongyu](https://forum.itascainternational.com/u/xiongyu)\ **Replies:** 4\ **Last updated:** [January 27, 2025, 8:04am UTC](https://forum.itascainternational.com/t/fish-for-the-fragment-in-udec/1067 "2025-01-27T08:04:04Z")
Hello I did not find any fish for the fragment in UDEC. How to iterating through all the fragment and find the specific fragment ID and calculate the volume or area of the specific fragment? --- ## [Block config cellspace n1 n2](https://forum.itascainternational.com/t/block-config-cellspace-n1-n2/1966)
**Author:** [@zack.tuckey](https://forum.itascainternational.com/u/zack.tuckey)\ **Replies:** 3\ **Last updated:** [February 28, 2025, 5:27pm UTC](https://forum.itascainternational.com/t/block-config-cellspace-n1-n2/1966 "2025-02-28T17:27:11Z")
Hi all, The cellspace contact detection logic in UDEC is invoked with “block config cellspace n1 n2” where n1 and n2 refer to the number of cells in the x- and y-directions. However, some examples show that the the n1 … --- ## [Heterogenous Contacts in UDEC](https://forum.itascainternational.com/t/heterogenous-contacts-in-udec/1724)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 2\ **Last updated:** [October 2, 2024, 2:02pm UTC](https://forum.itascainternational.com/t/heterogenous-contacts-in-udec/1724 "2024-10-02T14:02:01Z")
Hello all, I want to create a heterogenous contact heterogenous grain model in UDEC. I defined block grain groups and also defined contact groups after which this is the FISH code I wrote: fish define contact\_group ic… --- ## [Contact overlap too great on structural node interface](https://forum.itascainternational.com/t/contact-overlap-too-great-on-structural-node-interface/1716)
**Author:** [@Vijaybhvs](https://forum.itascainternational.com/u/Vijaybhvs)\ **Replies:** 1\ **Last updated:** [October 2, 2024, 1:50pm UTC](https://forum.itascainternational.com/t/contact-overlap-too-great-on-structural-node-interface/1716 "2024-10-02T13:50:36Z")
While deleting the blocks and applying either liner or rockbolts as support the message “Contact overlap too great on structural node interface” comes and the program stops while cycling. How to resolve this ? --- ## [How to plot stereonet plot in DFN UDEC](https://forum.itascainternational.com/t/how-to-plot-stereonet-plot-in-dfn-udec/1214)
**Author:** [@Binu](https://forum.itascainternational.com/u/Binu)\ **Replies:** 7\ **Last updated:** [July 3, 2024, 1:49pm UTC](https://forum.itascainternational.com/t/how-to-plot-stereonet-plot-in-dfn-udec/1214 "2024-07-03T13:49:57Z")
Hi, How to plot stereonet plot in DFN UDEC. I am getting only three option in DFN UDEC that is fracture, intersection and Rosette plots. --- ## [Query regarding use of block thermal substep in UDEC](https://forum.itascainternational.com/t/query-regarding-use-of-block-thermal-substep-in-udec/1562)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 0\ **Last updated:** [July 1, 2024, 12:06pm UTC](https://forum.itascainternational.com/t/query-regarding-use-of-block-thermal-substep-in-udec/1562 "2024-07-01T12:06:00Z")
Hello, I want to apply a thermo-coupled step on a block on which after heating the joints are broken(Thermal effects). I think block thermal substep is the way to achieve it. But I couldn’t understand how to go ahead … --- ## [Dynamic Analysis Contact Parameter Problem in UDEC](https://forum.itascainternational.com/t/dynamic-analysis-contact-parameter-problem-in-udec/1432)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 1\ **Last updated:** [May 2, 2024, 3:00pm UTC](https://forum.itascainternational.com/t/dynamic-analysis-contact-parameter-problem-in-udec/1432 "2024-05-02T15:00:56Z")
Hello everyone, I am performing a dynamic analysis test on SHPB Test Sample. I have attached a sample code for the same: model new block tolerance corner-round-length 3.4E-7 block tolerance minimum-edge-length 6.8E-4 … --- ## [Assigning different contact properties on different grains](https://forum.itascainternational.com/t/assigning-different-contact-properties-on-different-grains/1378)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 4\ **Last updated:** [March 27, 2024, 5:31pm UTC](https://forum.itascainternational.com/t/assigning-different-contact-properties-on-different-grains/1378 "2024-03-27T17:31:20Z")
Hello all, I just had a small query regarding assigning contact properties to a single grain. I used the block contact list information command in the console to obtain the complete list of all joints. A bit of whic… --- ## [Thermal analysis in UDEC to observe induced stress](https://forum.itascainternational.com/t/thermal-analysis-in-udec-to-observe-induced-stress/1381)
**Author:** [@SamVarun10](https://forum.itascainternational.com/u/SamVarun10)\ **Replies:** 2\ **Last updated:** [March 21, 2024, 3:01am UTC](https://forum.itascainternational.com/t/thermal-analysis-in-udec-to-observe-induced-stress/1381 "2024-03-21T03:01:50Z")
Hello everyone, I am new to Thermal Analysis at UDEC. I want to achieve thermal-induced stresses due to changes in temperature of a voronoi model. This is the following code I used: block config thermal block toleran… --- ## [Connect Rockbolt and Liner (Face plate)](https://forum.itascainternational.com/t/connect-rockbolt-and-liner-face-plate/1245)
**Author:** [@Akash](https://forum.itascainternational.com/u/Akash)\ **Replies:** 12\ **Last updated:** [December 11, 2023, 3:45pm UTC](https://forum.itascainternational.com/t/connect-rockbolt-and-liner-face-plate/1245 "2023-12-11T15:45:00Z")
Hello, I am trying to simulate rockbolt element connected to a faceplate in UDEC. The faceplate is constructed with the liner elements. I am trying to connect the rockbolt last node with the center node of the liner ele… --- ## [Wrong direction of displacements](https://forum.itascainternational.com/t/wrong-direction-of-displacements/1212)
**Author:** [@eduardocevallosc](https://forum.itascainternational.com/u/eduardocevallosc)\ **Replies:** 1\ **Last updated:** [October 16, 2023, 10:43am UTC](https://forum.itascainternational.com/t/wrong-direction-of-displacements/1212 "2023-10-16T10:43:31Z")
Hello everyone, I’m performing an excavation of a rock slope, I build the model, assigned material characteristics, assigned joins properties then I applied the in-situ stresses, assigned the boundary conditions to the s… --- ## [Increasing mechanical time step in thermal mechanical couple](https://forum.itascainternational.com/t/increasing-mechanical-time-step-in-thermal-mechanical-couple/1051)
**Author:** [@Binu](https://forum.itascainternational.com/u/Binu)\ **Replies:** 2\ **Last updated:** [October 14, 2023, 5:17pm UTC](https://forum.itascainternational.com/t/increasing-mechanical-time-step-in-thermal-mechanical-couple/1051 "2023-10-14T17:17:13Z")
The default time step in UDEC for mechanical analysis is in order of e-6. Can this mechanical time step increased to in order of 100 (e^2) like in thermal timestep where we can thermal time step to a big value. --- ## [UDEC - Contact length increase atomatically when smaller DFN intersected with Trigon](https://forum.itascainternational.com/t/udec-contact-length-increase-atomatically-when-smaller-dfn-intersected-with-trigon/1202)
**Author:** [@gaobo](https://forum.itascainternational.com/u/gaobo)\ **Replies:** 1\ **Last updated:** [October 6, 2023, 9:11am UTC](https://forum.itascainternational.com/t/udec-contact-length-increase-atomatically-when-smaller-dfn-intersected-with-trigon/1202 "2023-10-06T09:11:24Z")
I established a lab-scale specimen model, 5cm wide and 10cm high. The model is jointed through Trigon. The average size of trigon is 0.25cm. Then I introduced DFN, which intersected with Trigon. Size of DFN ranges from 0… --- ## [UDEC - Axial force plotting issue with Version 7.82](https://forum.itascainternational.com/t/udec-axial-force-plotting-issue-with-version-7-82/1077)
**Author:** [@Thiru28](https://forum.itascainternational.com/u/Thiru28)\ **Replies:** 1\ **Last updated:** [July 21, 2023, 8:12pm UTC](https://forum.itascainternational.com/t/udec-axial-force-plotting-issue-with-version-7-82/1077 "2023-07-21T20:12:39Z")
Hi There, I updated UDEC with version 7.82 updates. However, I am still having an issue with plotting axial forces in the rock bolt/cable. Please check and confirm this issue has been fixed. Kind regards Thiru --- ## [Applying linear varying temperature with height](https://forum.itascainternational.com/t/applying-linear-varying-temperature-with-height/899)
**Author:** [@Binu](https://forum.itascainternational.com/u/Binu)\ **Replies:** 2\ **Last updated:** [March 3, 2023, 12:21am UTC](https://forum.itascainternational.com/t/applying-linear-varying-temperature-with-height/899 "2023-03-03T00:21:02Z")
I want to apply linear varying temperature with height at boundary. I winder if I can use like this command where stress is linearly varied. block insitu stress -9.04E6 0 0 gradient-y 0.27 0 0 --- ## [Plane-stress method](https://forum.itascainternational.com/t/plane-stress-method/896)
**Author:** [@Jia](https://forum.itascainternational.com/u/Jia)\ **Replies:** 6\ **Last updated:** [February 6, 2023, 8:51pm UTC](https://forum.itascainternational.com/t/plane-stress-method/896 "2023-02-06T20:51:07Z")
Hi all, I wonder how to use plane-stress configuration with Hoek-Brown constitutive model for blocks. It seems like the command block config plane-stress is only applicable to the elastic and strain-softening models. Ma… --- ## [Grain Geometry Import and Group in UDEC](https://forum.itascainternational.com/t/grain-geometry-import-and-group-in-udec/910)
**Author:** [@Jia](https://forum.itascainternational.com/u/Jia)\ **Replies:** 1\ **Last updated:** [February 6, 2023, 5:45pm UTC](https://forum.itascainternational.com/t/grain-geometry-import-and-group-in-udec/910 "2023-02-06T17:45:44Z")
Hi all, I have imported dxf files as geometry in UDEC for different types of grains. Is there any way to cut the block by these grain dxf files and group them? Many thank. --- ## [UDEC convection and porous modeling](https://forum.itascainternational.com/t/udec-convection-and-porous-modeling/898)
**Author:** [@Binu](https://forum.itascainternational.com/u/Binu)\ **Replies:** 0\ **Last updated:** [January 25, 2023, 3:11pm UTC](https://forum.itascainternational.com/t/udec-convection-and-porous-modeling/898 "2023-01-25T15:11:40Z")
Hi everyone, I have following doubts I am doing thermal hydro modeling of a rockmass having joints, can we add thermal convection heat transfer in water by convection or equivalent conduction of convection in UDEC. … --- ## [Effective Voronoi size](https://forum.itascainternational.com/t/effective-voronoi-size/890)
**Author:** [@venkateshmd](https://forum.itascainternational.com/u/venkateshmd)\ **Replies:** 2\ **Last updated:** [January 17, 2023, 11:42am UTC](https://forum.itascainternational.com/t/effective-voronoi-size/890 "2023-01-17T11:42:39Z")
Hello, I have a model wherein I have used 5 mm Voronoi edge length and 3 mm joint spacing as shown below. Since joints are spaced 3 mm apart, Voronoi polygon side length will be less than 5 mm. Is there a way to find ef… [Next page](https://forum.itascainternational.com/c/udec/8.md?page=1)