Problem description

Normally, when you want to have an item activated you need to activate the checkmark in front of the item and set the values accordingly.
However, for the volume strain settings in PLAXIS 2D AE, PLAXIS 2D 2015.00 and PLAXIS 2D 2015.01 this does not always work as expected: whenever a value is set for one of the volume strain components (ε_xx, ε_yy, ε_zz and ε_vol), this will be applied in the calculation, independent of the activation state. This happens even if the volume strain components are not visible when the Apply checkbox is unchecked.

Solution

This issue is already solved since PLAXIS 2D 2015.02

When using an older version, you can manually check the behaviour of the volume strain settings by using the tabulate command to see if in any of the phases the volume strain values are not equal to zero:
tabulate Soils "VolumeStrain.epsvol"

With this, you could encounter a reply like this:

 0091>  tabulate Soils "VolumeStrain.epsvol" ObjectVolumeStrain.epsvol  Soil_1_Soil_2_1    InitialPhase: 0    Phase_1: 0    Phase_2: 0    Phase_3: 0    Phase_4: 1    Phase_5: 1    Phase_6: 1  Soil_1_1    InitialPhase: 0    Phase_1: 0    Phase_2: 0    Phase_3: 0    Phase_4: 0    Phase_5: 0    Phase_6: 0   

Here we can see that for the Soil object Soil_1_Soil_2_1 that the volume strain is set to 1 in Phases 4, 5 and 6. Now to conclude if the value is activated correctly, we should check the volume strain settings for this soil object in the selection explorer, see the examples below.

In these examples we see:

• Phase_4: Volume strain activated + applied is checked + values set. Now the volume strain is applied in the calculation
• Phase_5: Volume strain deactivated + applied is checked + values set. Now in PLAXIS 2D 2015.01 and earlier these values are incorrectly applied. 2D2015.02 and later works correctly: the volume strain is not applied as expected.
• Phase_6: Volume strain deactivated + applied is unchecked + values set (see command line results above). Now in PLAXIS 2D 2015.01 and earlier these values are incorrectly applied. 2D2015.02 and later works correctly: the volume strain is not applied as expected.

To summarize the behaviour:

Volume strain activated	Apply checked	Volume strain value	2D2015.01 and earlier	2D2015.02 and later
Yes	Yes	ε ≠ 0	✓ applied	✓ applied
Yes	No	ε ≠ 0	✘ applied	✓ not applied
No	Yes	ε ≠ 0	✘ applied	✓ not applied
No	No	ε ≠ 0	✘ applied	✓ not applied

 

In order to not have a volume strain applied in PLAXIS 2D 2015.01 and earlier, please manually set the values for the strain to zero for the individual clusters. To do so:

• check the Apply value to make the ε_xx, ε_yy, ε_zz and ε_vol parameters visible
• set these values to zero
• uncheck the Apply button