# \#flac2d **URL:** https://forum.itascainternational.com/tag/flac2d/15.md [Latest](https://forum.itascainternational.com/latest.md) · [Categories](https://forum.itascainternational.com/categories.md) · [Tags](https://forum.itascainternational.com/tags.md) --- ## [How to Start Post-Shake Consolidation After Compliant-Base Dynamic Analysis in FLAC2D?](https://forum.itascainternational.com/t/how-to-start-post-shake-consolidation-after-compliant-base-dynamic-analysis-in-flac2d/2386)
**Author:** [@EmirhanAltinok](https://forum.itascainternational.com/u/EmirhanAltinok)\ **Replies:** 5\ **Last updated:** [September 16, 2026, 5:46pm UTC](https://forum.itascainternational.com/t/how-to-start-post-shake-consolidation-after-compliant-base-dynamic-analysis-in-flac2d/2386 "2026-09-16T17:46:39Z")
Hello all, I am performing nonlinear dynamic effective-stress SSI analyses in FLAC2D 9.0 using PM4Sand and PM4Silt. The model includes two buildings represented by elastic beam elements. The earthquake motion is applied … --- ## [Applying Time-Varying Non-Uniform Surface Pressure in FLAC3D](https://forum.itascainternational.com/t/applying-time-varying-non-uniform-surface-pressure-in-flac3d/2390)
**Author:** [@Sudipta](https://forum.itascainternational.com/u/Sudipta)\ **Replies:** 0\ **Last updated:** [June 2, 2026, 5:18pm UTC](https://forum.itascainternational.com/t/applying-time-varying-non-uniform-surface-pressure-in-flac3d/2390 "2026-06-02T17:18:27Z")
Hello everyone and Itasca support team, @itascaYang @isaac @itsmoho\_sen @ITE @Inwoo @Inu @itmam @itasca @dafo407\_itasca @dblanksma I am trying to apply a time-varying non-uniform distributed pressure on a surface in FL… --- ## [Questions About Fully Coupled Flow–Mechanical Analysis and Solution-Control Parameters in FLAC3D](https://forum.itascainternational.com/t/questions-about-fully-coupled-flow-mechanical-analysis-and-solution-control-parameters-in-flac3d/2389)
**Author:** [@Sudipta](https://forum.itascainternational.com/u/Sudipta)\ **Replies:** 0\ **Last updated:** [June 1, 2026, 3:48pm UTC](https://forum.itascainternational.com/t/questions-about-fully-coupled-flow-mechanical-analysis-and-solution-control-parameters-in-flac3d/2389 "2026-06-01T15:48:49Z")
Hello @everyone, @itascaYang @isaac @itsmoho\_sen @ITE @Inwoo @Inu @itasca @dafo407\_itasca @itascan I am planning to perform a fully coupled flow–mechanical analysis in FLAC3D. My current understanding of the command seq… --- ## [Boundary conditions for soil block](https://forum.itascainternational.com/t/boundary-conditions-for-soil-block/2379)
**Author:** [@William](https://forum.itascainternational.com/u/William)\ **Replies:** 1\ **Last updated:** [April 22, 2026, 4:08pm UTC](https://forum.itascainternational.com/t/boundary-conditions-for-soil-block/2379 "2026-04-22T16:08:15Z")
Hello I am currently working with the automatic remeshing feature in FLAC2D. I want to model a soil block and allow it to fail towards the left. However, I am unsure how to properly define boundary conditions in the … --- ## [Post liquefaction residual strength](https://forum.itascainternational.com/t/post-liquefaction-residual-strength/2214)
**Author:** [@Milads](https://forum.itascainternational.com/u/Milads)\ **Replies:** 2\ **Last updated:** [August 28, 2025, 5:13pm UTC](https://forum.itascainternational.com/t/post-liquefaction-residual-strength/2214 "2025-08-28T17:13:38Z")
I am running a 1D seismic site response analysis with FLAC 2D v8.1 and would like to know whether it is possible to extract the post-liquefaction residual strength directly from the model. I am using the PM4Sand and PM4S… --- ## [Short-Period Spike in PSA from Plastic Hardening Model](https://forum.itascainternational.com/t/short-period-spike-in-psa-from-plastic-hardening-model/2192)
**Author:** [@EmirhanAltinok](https://forum.itascainternational.com/u/EmirhanAltinok)\ **Replies:** 2\ **Last updated:** [August 10, 2025, 7:48pm UTC](https://forum.itascainternational.com/t/short-period-spike-in-psa-from-plastic-hardening-model/2192 "2025-08-10T19:48:35Z")
Hi everyone, I performed a zone test to compare the Plastic Hardening model in FLAC2D with the HS-Small model in Plaxis 2D. To do this, I set up a 1D single-column soil model composed of 5 zones, representing a 5-meter-… --- ## [Strange PSA Amplification in FLAC Plastic Hardening vs Plaxis HS-Small in 1D Model](https://forum.itascainternational.com/t/strange-psa-amplification-in-flac-plastic-hardening-vs-plaxis-hs-small-in-1d-model/2128)
**Author:** [@EmirhanAltinok](https://forum.itascainternational.com/u/EmirhanAltinok)\ **Replies:** 3\ **Last updated:** [June 18, 2025, 3:08pm UTC](https://forum.itascainternational.com/t/strange-psa-amplification-in-flac-plastic-hardening-vs-plaxis-hs-small-in-1d-model/2128 "2025-06-18T15:08:01Z")
Hi all, I’m running a 1D site response analysis consisting of 8 horizontal layers. The top 7 layers are modeled using PM4Sand and PM4Silt, and the bottom layer (Layer 8) uses the Plastic Hardening (PH) model in FLAC2D, … --- ## [Plastic-Hardening model: Internal parameter calculation fails (small-strain active)](https://forum.itascainternational.com/t/plastic-hardening-model-internal-parameter-calculation-fails-small-strain-active/2110)
**Author:** [@EmirhanAltinok](https://forum.itascainternational.com/u/EmirhanAltinok)\ **Replies:** 2\ **Last updated:** [June 4, 2025, 6:30pm UTC](https://forum.itascainternational.com/t/plastic-hardening-model-internal-parameter-calculation-fails-small-strain-active/2110 "2025-06-04T18:30:28Z")
Hi all, I’m currently using FLAC2D v9 to implement the Plastic-Hardening constitutive model with small-strain stiffness activated. However, I consistently receive the following error : \*\*\* Plastic-Hardening model: Inter… --- ## [Strange PWP Ratio Response in 1D Analysis Compared to 2D Version](https://forum.itascainternational.com/t/strange-pwp-ratio-response-in-1d-analysis-compared-to-2d-version/2094)
**Author:** [@EmirhanAltinok](https://forum.itascainternational.com/u/EmirhanAltinok)\ **Replies:** 4\ **Last updated:** [May 27, 2025, 11:51am UTC](https://forum.itascainternational.com/t/strange-pwp-ratio-response-in-1d-analysis-compared-to-2d-version/2094 "2025-05-27T11:51:54Z")
Hello all, I am currently performing a 1D site response analysis using FLAC 2D. My model consists of eight soil layers: the top seven layers are defined with PM4Sand and PM4Silt, while the bottom (eighth) layer is model… --- ## [Plotting Gridpoint Groups](https://forum.itascainternational.com/t/plotting-gridpoint-groups/1862)
**Author:** [@ddegagne](https://forum.itascainternational.com/u/ddegagne)\ **Replies:** 0\ **Last updated:** [December 19, 2024, 5:39pm UTC](https://forum.itascainternational.com/t/plotting-gridpoint-groups/1862 "2024-12-19T17:39:45Z")
In FLAC3D and FLAC2D you can plot contours of gridpoint data (e.g. displacement) and zone groups, however there is currently no built-in way to show gridpoint labels (e.g. groups). However, you can do this by creating an…