On Calibrating PM4 models, how to generate g/gmax vs strain graph and damping vs strain graph, using soil testing to adjust the secondary parameters.?
On Calibrating PM4 models, how to generate g/gmax vs strain graph and damping vs strain graph, using soil testing to adjust the secondary parameters.?
Interpreting interface results in tables
Application
PLAXIS 2D PLAXIS 3D
Version
PLAXIS 2D PLAXIS 3D
Date created
25 August 2023
Date modified
25 August 2023
Original author
Vasileios Basas - Bentley Technical Support Group
When viewing nodal interface…
PLAXIS 2D Tutorial: Stabilisation of a rock slope
Application
PLAXIS 2D
Version
PLAXIS 2D
Date created
25 Aug 2023
Date modified
25 Aug 2023
This tutorial illustrates the use of PLAXIS 2D for simulating the excavation of a road cut in a siltstone rock mass with…
Local failure in the backfill surface when modelling a simple cantilever wall
When I model a simple cantilever wall without any kind of lack of stability, I always get a nonsense local failure in the surface of the backfilling, in the contact with the concrete, which stops the calculations. I have wasted a lot of time tryng to…
To perform dynamic analysis should the displacements be reset to zero, as well as the small deformations?
To perform dynamic analysis (seismic analysis) of an underground structure in Plaxis 2D, should the displacements be reset to zero, as well as the small deformations?, considering that there are previous stages or phases of construction and service (static…
How can I overcome/rectify this void around the tunnel?
Hello,
I modeled a tunnel of 2.5 m in the soil layer. In the calculation result at the lining stage voids are created around the pipe. How can I remove these voids? what is the reason behind this phenomenon? Many thanks for your help.
Liquefaction Points in the Dynamic Analysis
Dear sir/madam,
I'm working on a dynamic analysis model to check liquefaction potential of a multilayered soil profile. When i looked at the Ru values at the end of analysis and compare them with the Ru values at the intermediate steps during the earthquake…
The pore water pressure above the tunnel is observed to be positive that results into negative ru, excess pore water pressure ratios.
The pore water pressure above the tunnel is observed to be positive under dynamic loading that results into negative ru, excess pore water pressure ratios. What could be the reason? kindly help me
On using PM4silt for clay and using Undrained A and for sandy soils (PM4sand) Undrained A.is it correct to use this combination while studying for liquefaction analysis?
On using PM4silt for clay and using Undrained A and for sandy soils (PM4sand) Undrained A.is it correct to use this combination while studying for liquefaction analysis?
UBC3D Liquefaction Model
Dear sir/madam,
I have a question about UBC3D model for my dynamic analysis model:
Does the "G" parameter (Elastic shear modulus, which is calculated by the kGe shear modulus factor) equal to G0=(Vs^2*(Unit weight/g))? If so, isn't this model…
UBC3D Model in Dynamic Analysis with Liquefaction Check
Dear sir/madam,
I'm working on a dynamic analysis of a multilayered soil profile improved with stone columns & piles. I have some questions regarding the parameters:
While using the UBC3D model for liquefaction, we know that it overestimates the shear…
Liquefaction Check in Dynamic Analysis
Dear sir/madam,
I'm working on a dynamic analysis in a multilayered soil profile improved with stone colums & piles. I have some questions regarding this analysis:
1) To evaluate the liquefaction, i should use the dynamic with consolidation calculation…
Rock Outcrop Motion Comparison of Plaxis and FLAC 2D
Dear sir/madam,
In the Plaxis manuals, it is stated that input motion should be factored by 0.5 if the applied input motion is rock outcrop motion and compliant base boundary is used at the bottom boundary.
If we use an rock outcrop earthquke record…
Rock Outcrop Motion 0.5 Factor
Dear sir/madam,
I have a simple question about the usage of rock outcrop input motion in dynamic analysis with compliant base boundary:
1) Using a line displacement with u=0.5 and input motion as its current situation
2) Scaling the input motion…
Acceleration and Structural Force Difference Between the Piles Modeled with Embedded Beam and Plate
Dear sir/madam,
I'm studying on a dynamic analysis model consist of nonhomogeneous soil layers improved with stone columns and rock socketed piles connected to raft foundation. I'm using two models:
1) Piles modeled with embedded beam row
2) Piles…
Sudden Displacement and Structural Force Increase at the End of Earthquake
Dear sir/madam,
I'm studying on an earthquake analysis with Plaxis 2D (with an input motion whose duration is almost 12s). While acceleration values goes around 0m/s^2 after 8s (drift correction is applied), there is a sudden and significant increase…
Limits in slopes for PLAXIS 2D
Hi,
Is there a way of restrict the failure slope that PLAXIS 2D give me? For example in an earth dam I want that my slip mass for a pseudostatic analysis starts in the crest, is there a way to do that?
Thanks
Interface stiffness defined by "Direct"
Dear Support Team,
When I applied extremely low ks & kn values for a sensitivity check, I found a gap at the interface before activating the interface element .
I suspect that ks & kn values defined by "direct" are applied to the interface element…
How to measure uplift in a tunnel embedded in saturated soil?
How to measure uplift in a tunnel due to liquefaction in PLAXIS 2D?
Plastic Points in Dynamic Analysis
Dear sir/madam,
Is it normal to have plastic points in the model at the end of a dynamic analysis like in the figure i shared below? I'm facing with this situation in some of the earthquake records, but not all of them. When i tried another earthquake…
Rayleigh Damping in Plaxis 2D
Dear sir/madam,
I have two questions about the usage of rayleigh damping,
1) How should we assign the rayleigh damping coefficients in layered soils? I mean that sohuld we determine the f1 and f2 values for each layer or should we determine uniform…
Material replacement and fixed displacement
Hello，
If in phase 1, there are two layers of soil in the model, but in phase 2, I need to replace the material of the upper soil with concrete, and at the same time, at this stage, I do not want this layer of concrete to cause any pressure on the lower…
Structure Mode Shape
Is there a way in PLAIXS 2D that can obtain the mode shape of the structure?
How to simulate cyclic triaxial test in Plaxis software? Is there any particular example video for the same?
How to simulate cyclic triaxial test in Plaxis software? Is there any particular example video for the same? And how can I observe pore pressure ratio with time?
Plaxis Dynamic Analysis Rock Outcrop Motion
Dear sir/madam,
I have a question about the rock outcrop motion in dynamic analysis. When the input motion is a rock outcrop motion, we should scale this motion by 0.5 for the compliant base boundary. But, i'm wondering about if we can make deconvolution…