# SOft soil creep model Displacement plot **URL:** \ **Category:** FLAC3D\ **Created:** [July 13, 2025, 3:12pm UTC](https://forum.itascainternational.com/t/soft-soil-creep-model-displacement-plot/2160 "2025-07-13T15:12:21Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![sowmyaramanis](https://avatars.discourse-cdn.com/v4/letter/s/839c29/32.png) [@sowmyaramanis](https://forum.itascainternational.com/u/sowmyaramanis)\ **Post date:** [July 13, 2025, 3:12pm UTC](https://forum.itascainternational.com/t/soft-soil-creep-model-displacement-plot/2160/1 "2025-07-13T15:12:21Z")
I have tried to get the dispalcement variation with time of a unit cell model of sof clay improved my cement columns. I am getting the displacement curve but the slope of the displacement curve changes beyond a point. Not sure why this happens. I have used the creep parameters same as that of the example problem given in flac. I have also attached the curve and the code for reference. Kindly let me know what has to be modified. ![image](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/2X/c/c52f6cfab5aa036af63ad985224a239713a65f34.png) Dat file: model new model title “coupled\_06” model large-strain off fish automatic-create off model configure fluid creep ; zone create cylinder point 0 (0,0,0) point 1 (1.275,0,0) point 2 (0,5,0) point 3 (0,0,1.275) size 6 5 6 group ‘soil’ zone group ‘column’ range cylinder end-1 (0 0 0) end-2 (0 5 0) radius 0.425 zone face skin zone cmodel assign soft-soil-creep range group ‘soil’ zone property density 617 lambda-modified 0.095 kappa-modified 0.015 range group ‘soil’ zone property poisson 0.33 friction 1 range group ‘soil’ zone property index-creep 0.0076 time-reference 2200 range group ‘soil’ zone property void-initial 3.3 range group ‘soil’ zone property stress-1-eff -20e3 stress-2-eff -10e3 stress-3-eff -10e3 range group ‘soil’ zone cmodel assign m-c range group ‘column’ zone property bulk 120e5 shear 46e5 cohesion 32e3 friction 1 poisson 0.33 range group ‘column’ zone property density 629 range group ‘column’ zone face apply velocity-z 0 range group ‘bottom’ zone face apply velocity-x 0 range group ‘west’ zone face apply velocity-x 0 range group ‘east’ zone face apply velocity-z 0 range group ‘east’ zone face apply velocity (0,0,0) range group “south” zone initialize stress-xx -10e3 zone initialize stress-yy -20e3 zone initialize stress-zz -10e3 ; — fluid flow model — zone fluid cmodel assign isotropic zone fluid property permeability 1.62e-10 porosity 0.76 range group ‘soil’ zone fluid property perm 4.04e-10 poro 0.76 range group ‘column’ zone gridpoint initialize saturation 1.0 zone gridpoint initialize fluid-modulus 2e8 zone gridpoint initialize pore-pressure 0 zone initialize fluid-density 1e3 ; model fluid active off model creep active off ; apply load zone face apply stress-yy -100e3 servo ramp minimum [1.0/11] range position-y 5 model solve ratio 1e-7 model save ‘coupled\_06\_initial’ ; fish define set\_creep command model creep timestep starting 1e-16 model creep timestep automatic model creep timestep minimum 1e-16 model creep timestep maximum 1000 end\_command end ; — histories — model history fluid time-total zone history name ‘soil’ pore-pressure position ( 0.676171, 0, 0.676171) zone history name ‘mid’ pore-pressure position ( 0.243961, 0, 0.588973) zone history name ‘middle’ displacement-y position ( 0.676171, 5, 0.676171) zone history name ‘soil corner’ displacement-y position ( 0.243961, 5, 0.588973) ; model fluid active on model fluid time-total 0.0 ; model creep active on model creep time-total 0.0 ; zone face apply pore-pressure 0 range position-y 5 ; [set\_creep] model solve fluid time-total 8e6 model save ‘coupled\_06\_end’ ---
**Author:** ![cheng](https://avatars.discourse-cdn.com/v4/letter/c/ecccb3/32.png) [@cheng](https://forum.itascainternational.com/u/cheng)\ **Post date:** [July 14, 2025, 3:41pm UTC](https://forum.itascainternational.com/t/soft-soil-creep-model-displacement-plot/2160/2 "2025-07-14T15:41:52Z")
Looks like it is the effect of secondary consolidation (compression). Please check the doc of [Soft-Soil-Creep model](https://docs.itascacg.com/itasca900/common/models/softsoilcreep/doc/modelsoftsoilcreep.html?node1324), and [this example](https://docs.itascacg.com/itasca900/flac3d/zone/test3d/ExampleApplications/1DConsolidationSecondaryCompression/1DConsolidationSecondaryCompression.html#onedcons2ndcomp). ---
**Author:** ![sowmyaramanis](https://avatars.discourse-cdn.com/v4/letter/s/839c29/32.png) [@sowmyaramanis](https://forum.itascainternational.com/u/sowmyaramanis)\ **Post date:** [July 28, 2025, 5:11pm UTC](https://forum.itascainternational.com/t/soft-soil-creep-model-displacement-plot/2160/3 "2025-07-28T17:11:44Z")
model new model title “igc\_c2” model large-strain off fish automatic-create off model configure fluid creep ; zone create cylinder point 0 (0,0,0) point 1 (1.275,0,0) point 2 (0,5,0) point 3 (0,0,1.275) size 4 5 4 group ‘soil’ zone face skin zone cmodel assign soft-soil-creep zone property lambda-modified 0.107 kappa-modified 0.00169 zone property poisson 0.33 friction 1 zone property index-creep 0.128 time-reference 2200 zone property void-initial 4.5 zone property stress-1-eff -20e3 stress-2-eff -10e3 stress-3-eff -10e3 zone face apply velocity-z 0 range group ‘bottom’ zone face apply velocity-x 0 range group ‘west’ zone face apply velocity-x 0 range group ‘east’ zone face apply velocity-z 0 range group ‘east’ zone face apply velocity (0,0,0) range group “south” zone initialize stress-xx -10e3 zone initialize stress-yy -20e3 zone initialize stress-zz -10e3 ; — fluid flow model — zone fluid cmodel assign isotropic zone fluid property permeability 3.79e-15 zone gridpoint initialize saturation 1.0 zone gridpoint initialize fluid-modulus 2e8 zone gridpoint initialize pore-pressure 0 zone initialize fluid-density 1e3 ; model fluid active off model creep active off ; apply load zone face apply stress-yy -100e3 servo ramp minimum [1.0/11] range position-y 5 model solve ratio 1e-7 model save ‘igc\_c2\_t1\_ini’ ; fish define set\_creep command model creep timestep starting 1e-16 model creep timestep automatic model creep timestep minimum 1e-16 model creep timestep maximum 1000 end\_command end ; — histories — model history fluid time-total zone history name ‘soil’ pore-pressure position ( 0.676171, 0, 0.676171) zone history name ‘mid’ pore-pressure position ( 0.243961, 0, 0.588973) zone history name ‘middle’ displacement-y position ( 0.676171, 5, 0.676171) zone history name ‘soil corner’ displacement-y position ( 0.243961, 5, 0.588973) ; model fluid active on model fluid time-total 0.0 ; model creep active on model creep time-total 0.0 ; zone face apply pore-pressure 0 range position-y 5 ; [set\_creep] model solve fluid time-total 8e8 model save ‘igc\_c2\_t1\_end’ In the above code, while running the model solve fluid time-total 8e8, I am getting an error saying, “timestep too large for the ssc model”. However I am kept the timestep as automatic only. Still error occurs. how can it be rectified? ---
**Author:** ![sowmyaramanis](https://avatars.discourse-cdn.com/v4/letter/s/839c29/32.png) [@sowmyaramanis](https://forum.itascainternational.com/u/sowmyaramanis)\ **Post date:** [July 28, 2025, 5:21pm UTC](https://forum.itascainternational.com/t/soft-soil-creep-model-displacement-plot/2160/4 "2025-07-28T17:21:43Z")
Also, when the minimum and maximum values were commented, the error says " starting timestep should not be geater than the maximum timestep". So when I commented the starting timestep value, the simulation is progressing, but it is very slow taking a huge time.