Forces in plates using elastoplastic M-kappa diagram not correct in a Target SumMsf Safety calculati

ApplicationPLAXIS 2D
Issue status✔ Solved
First Affected VersionPLAXIS 2D 2015.00
Found in VersionPLAXIS 2D 2015.00
Fixed and Released in VersionPLAXIS 2D 2015.01
Issue #23426
Date created07 April 2015
Date modified24 October 2016

Problem description

When performing a Safety analysis with a Target Factor of Safety (ΣMsf), the calculation will first pass the target value to ensure that this ΣMsf value is a “stable” value before returning to the specified target value, see also the related article on Safety calculation with a Target Value for more background information.
In PLAXIS 2D 2015.00, when the calculation jumps back to the calculation step prior to reaching the target value, the internal stresses to determine the location in the M-kappa diagram are not (re)set to this calculation step (point C in the image below), but are still taken from the step with a higher ΣMsf (point B) before performing the final calculation step (point D). As a result, the plate’s forces are not correct for this final step of the Safety analysis with a Target ΣMsf.



This is now fixed in PLAXIS 2D 2015.01

For PLAXIS 2D 2015.00, some work arounds are mentioned below:

Obtain correct force values

To find the correct forces in the embedded pile row, the step in which the value for ΣMsf is equal to the value for the Target ΣMsf should be manually determined and then inspected:

Continue calculation

To continue phases from this situation with the correct value of ΣMsf:

Note, this is now fixed in PLAXIS 2D 2015.01