Problem description

With the first release of the PLAXIS Soiltest Parameter optimisation in PLAXIS 2D2012.00, some issues were found:

Intensity of search: Moderate and thorough

Due to an internal crash in the parameter optimisation kernel, the search using a moderate or thorough search intensity gives less accurate results than when using a coarse and quick search.

Some input parameters are not recognized

In the parameter optimisation program, after selecting one of the mentioned parameters below in the “import curve” window, the error “wrong material parameter in curve file” is shown. The error is caused by the fact that the optimisation kernel does not recognise the following input parameters.

Parameters that cause the error message:

• (σ’₁ – σ’₃)/2
• τ (tau)
• σ’
• ε₂
• ε₃

Graphical display of charts

Although the graphs represent the correct numbers, from a geotechnical perspective some axes should be flipped to be more recognizable, especially since these axes are flipped when seeing the results for a normally run soiltest.

An example: typically ε₁ has only negative values (compression), but it’s custom to plot them with the zero at the origin left, and values increasingly negative to the right. In this first release however, the axis is plotted with the zero at the origin right and increasingly negative to the left.

Opening path for import curve is not remembered

When importing an external curve file into the parameter optimization, users may notice that the file requester always fall back to the Plaxis installation folder. This is inconvenient when importing more than one curve when doing the parameter optimization.
A simple workaround for when multiple curve data files are stored in the same folder, would be to first copy the curve data file path to the clipboard, and then paste the path into the file requester every time a new curve is to be imported.

Solution

These above mentioned issues are fixed in PLAXIS 2D 2012.01:

• Intensity of search: Moderate and thorough. This is fixed now, but be aware that moderate and especially thorough searches take noticeably more time.
• Some input parameters are not recognized. These parameters are now recognized.
• Opening path for import curve is not remembered. It is now remembered

The flipping of the axis (issue Graphical display of charts) is not yet fixed in PLAXIS 2D 2012.01