# FLAC **URL:** https://forum.itascainternational.com/c/flac/7.md?page=2 [Latest](https://forum.itascainternational.com/latest.md) · [Categories](https://forum.itascainternational.com/categories.md) · [Tags](https://forum.itascainternational.com/tags.md) **Page:** 3 --- ## [Question for Unit of Structure load](https://forum.itascainternational.com/t/question-for-unit-of-structure-load/1149)
**Author:** [@PeterLee](https://forum.itascainternational.com/u/PeterLee)\ **Replies:** 2\ **Last updated:** [August 29, 2023, 11:19pm UTC](https://forum.itascainternational.com/t/question-for-unit-of-structure-load/1149 "2023-08-29T23:19:29Z")
Hi All~ Just I have a question for Unit of Structure node. As you know, when we apply any force on Structure elements, we use node command like below. ‘Structure node n load fx fy mom’ in this case, what is unit for … --- ## [Movie Viewer (Extension for FLAC)](https://forum.itascainternational.com/t/movie-viewer-extension-for-flac/1088)
**Author:** [@CrissBidermann](https://forum.itascainternational.com/u/CrissBidermann)\ **Replies:** 1\ **Last updated:** [July 24, 2023, 3:00pm UTC](https://forum.itascainternational.com/t/movie-viewer-extension-for-flac/1088 "2023-07-24T15:00:43Z")
I wanted to ask about the “Movie Viewer” extension for FLAC, which is available for download on the ITASCA page. What does it consist of? What benefits does it offer? How is it used? --- ## [Two phase flow in FLAC](https://forum.itascainternational.com/t/two-phase-flow-in-flac/170)
**Author:** [@xiongyu](https://forum.itascainternational.com/u/xiongyu)\ **Replies:** 1\ **Last updated:** [February 2, 2022, 9:18pm UTC](https://forum.itascainternational.com/t/two-phase-flow-in-flac/170 "2022-02-02T21:18:00Z")
i use two-phase flow option in FLAC 8.0 version to simulate carbon dioxide injection into the deep ground undersea floor. When the “udcoe” is initialized to 0 in my model, all the results seem reasonable except the disp… --- ## [FLAC 9.0 UDM models and water pressure](https://forum.itascainternational.com/t/flac-9-0-udm-models-and-water-pressure/955)
**Author:** [@song](https://forum.itascainternational.com/u/song)\ **Replies:** 6\ **Last updated:** [March 14, 2023, 4:32pm UTC](https://forum.itascainternational.com/t/flac-9-0-udm-models-and-water-pressure/955 "2023-03-14T16:32:28Z")
We have updated to FLAC 9.0 and would like to confirm the following two questions: Is UDM models (i.e. UBCSAND or PM4SAND) available in FLAC2d 9.0? If grid configured for water flow? Can I use zone water set to set up … --- ## [FLAC GUI sys error](https://forum.itascainternational.com/t/flac-gui-sys-error/794)
**Author:** [@jwang](https://forum.itascainternational.com/u/jwang)\ **Replies:** 0\ **Last updated:** [October 24, 2022, 9:33pm UTC](https://forum.itascainternational.com/t/flac-gui-sys-error/794 "2022-10-24T21:33:40Z")
In FLAC, you may get a GUI error saying ‘\> sys cd ‘C\\Program Files \\Itasca\\FLAC810’ ; $ Missing quote at end of command line’ and then unable to work on GUI. There are two ways to fix this: Option 1: Go to FLAC ins… --- ## [Help needed: Modeling an Excavation in Clay with Mohr-Coulomb Model](https://forum.itascainternational.com/t/help-needed-modeling-an-excavation-in-clay-with-mohr-coulomb-model/774)
**Author:** [@stmicheljerome](https://forum.itascainternational.com/u/stmicheljerome)\ **Replies:** 3\ **Last updated:** [October 10, 2022, 5:55pm UTC](https://forum.itascainternational.com/t/help-needed-modeling-an-excavation-in-clay-with-mohr-coulomb-model/774 "2022-10-10T17:55:13Z")
Hi there, I’m trying to model an excavation in clay using FLAC2D. The stratigraphy goes as follow, 27m of clay, purple zones, laying on the bedrock, green zone. Here is my mesh: Gravity is taken to be 9.81m/s2, unit… --- ## [User Defined Model for Dynamic Analysis in FLAC / FLAC3D](https://forum.itascainternational.com/t/user-defined-model-for-dynamic-analysis-in-flac-flac3d/722)
**Author:** [@FLAC3D\_GEO](https://forum.itascainternational.com/u/FLAC3D_GEO)\ **Replies:** 7\ **Last updated:** [September 19, 2022, 5:42pm UTC](https://forum.itascainternational.com/t/user-defined-model-for-dynamic-analysis-in-flac-flac3d/722 "2022-09-19T17:42:33Z")
We are developing C++ UDM to model nonlinear stress-strain behaviour including the unload-reload hysteresis using the Mohr-coulomb (or elastic) model as the basis. This was achieved by updating the shear modulus (shear) … --- ## [Undrained strength ratio with strain softening](https://forum.itascainternational.com/t/undrained-strength-ratio-with-strain-softening/624)
**Author:** [@Gian](https://forum.itascainternational.com/u/Gian)\ **Replies:** 3\ **Last updated:** [June 24, 2022, 2:29pm UTC](https://forum.itascainternational.com/t/undrained-strength-ratio-with-strain-softening/624 "2022-06-24T14:29:08Z")
Hello guys, I understand that the strain-softening (SS) model uses tables to describe post-peak strength and that the number of tables could be limited. Would you think in any way of considering spatially variable prope… --- ## [Added Mass in FLAC for dynamic soil-structure-water interaction](https://forum.itascainternational.com/t/added-mass-in-flac-for-dynamic-soil-structure-water-interaction/555)
**Author:** [@FLAC3D\_GEO](https://forum.itascainternational.com/u/FLAC3D_GEO)\ **Replies:** 5\ **Last updated:** [May 26, 2022, 1:57pm UTC](https://forum.itascainternational.com/t/added-mass-in-flac-for-dynamic-soil-structure-water-interaction/555 "2022-05-26T13:57:23Z")
Hi All, Is there any way to apply different masses in different directions (horizontal and vertical) in FLAC to perform seismic soil-structure interaction underwater? The structure will be modelled with beams. Apparently… --- ## [FLAC2D Launch Upcoming](https://forum.itascainternational.com/t/flac2d-launch-upcoming/439)
**Author:** [@dajwahl](https://forum.itascainternational.com/u/dajwahl)\ **Replies:** 5\ **Last updated:** [April 13, 2022, 7:15pm UTC](https://forum.itascainternational.com/t/flac2d-launch-upcoming/439 "2022-04-13T19:15:09Z")
Just saw that FLAC will be phased out and a new replacement called FLAC2D is going to be launched shortly. Will all CPPUDMs already compiled for FLAC have to be recompiled for FLAC2D? In particular we use PM4Sand and P… --- ## [Run control and queuing](https://forum.itascainternational.com/t/run-control-and-queuing/437)
**Author:** [@dajwahl](https://forum.itascainternational.com/u/dajwahl)\ **Replies:** 2\ **Last updated:** [April 12, 2022, 8:16pm UTC](https://forum.itascainternational.com/t/run-control-and-queuing/437 "2022-04-12T20:16:22Z")
Just curious how people generally do run control or queuing when conducting multiple analysis runs for evaluation of sensitivity/uncertainty, or dynamic inputs, etc. Our most common situation is earthquake analysis wher… --- ## [What will be reset when I switch from Mohr-coulomb model to Strain-softening?](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398)
**Author:** [@FLAC3D\_GEO](https://forum.itascainternational.com/u/FLAC3D_GEO)\ **Replies:** 4\ **Last updated:** [March 30, 2022, 1:49am UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398 "2022-03-30T01:49:20Z")
Hi, Could anyone inside Itasca clarify what will be changed when I switch the soil model from mohr-coulomb to the strain-softening model in FLAC? In FLAC3D, it seems to me that the stress won’t reset, and I do not need t… --- ## [Periodic boundary condition in FLAC?](https://forum.itascainternational.com/t/periodic-boundary-condition-in-flac/387)
**Author:** [@Hadi](https://forum.itascainternational.com/u/Hadi)\ **Replies:** 1\ **Last updated:** [March 28, 2022, 2:14pm UTC](https://forum.itascainternational.com/t/periodic-boundary-condition-in-flac/387 "2022-03-28T14:14:59Z")
Is it possible in FLAC to have a similar type of periodic boundary condition that exists in PFC? To be able to connect zones and gridpoints on one side of the domain to the other side of the domain? --- ## [Two phase coupling FLAC 8.0](https://forum.itascainternational.com/t/two-phase-coupling-flac-8-0/353)
**Author:** [@xiongyu](https://forum.itascainternational.com/u/xiongyu)\ **Replies:** 0\ **Last updated:** [March 14, 2022, 11:28pm UTC](https://forum.itascainternational.com/t/two-phase-coupling-flac-8-0/353 "2022-03-14T23:28:17Z")
I use the command “interior nwwell 0.0005 i=2, j= 3” to represent sources of C02 injection with a target volume rate of 0.0005m3/second in-situ at zone i=2, j= 3. Should the volume rate (0.0005) further divided by the… --- ## [Range 'Smart regions' option in FLAC GUI](https://forum.itascainternational.com/t/range-smart-regions-option-in-flac-gui/112)
**Author:** [@jwang](https://forum.itascainternational.com/u/jwang)\ **Replies:** 0\ **Last updated:** [September 23, 2021, 8:10pm UTC](https://forum.itascainternational.com/t/range-smart-regions-option-in-flac-gui/112 "2021-09-23T20:10:15Z")
When specifying material properties or some initial conditions, you may choose to use the ‘region’ option, however, in some models, the attach/interface lines can introduce discontinuities for the regions. If the same … --- ## [Out of Memory Java related error](https://forum.itascainternational.com/t/out-of-memory-java-related-error/107)
**Author:** [@jwang](https://forum.itascainternational.com/u/jwang)\ **Replies:** 0\ **Last updated:** [September 21, 2021, 9:50pm UTC](https://forum.itascainternational.com/t/out-of-memory-java-related-error/107 "2021-09-21T21:50:15Z")
The following Java error may show up when running very large model with many history plots created in GUI To fix this issue, in FLAC8.1 just go to File-\>Memory settings, increase the GUI memory.: In FLAC8 and previ… --- ## [Use z\_model(),z\_prop() and z\_group(). to access model and properties](https://forum.itascainternational.com/t/use-z-model-z-prop-and-z-group-to-access-model-and-properties/106)
**Author:** [@jwang](https://forum.itascainternational.com/u/jwang)\ **Replies:** 0\ **Last updated:** [September 21, 2021, 9:13pm UTC](https://forum.itascainternational.com/t/use-z-model-z-prop-and-z-group-to-access-model-and-properties/106 "2021-09-21T21:13:59Z")
1.To access CPP (CPP built-in and CPPUDM) models and their properties: Use: z\_model() to return or modify model name. e.g. if z\_model(i,j)=‘finn’ z\_prop() to access property name. e.g. \_fric=z\_prop(i,j,‘friction’) T… [Previous page](https://forum.itascainternational.com/c/flac/7.md?page=1)