When a concrete roof slab (plate) is just installed in Plaxis the horizontal phase displacement of this plate is aprox 0.2 mm and the difference along the length of the plate is aprox. 0.02 mm, see figure below. This is according to our exceptation.
But the total displacements seem not logical. Because this is the first phase that the plate is installed we would expect the total displacement to be equal to the phase displacement, which is not the case, see figure below. Then I thought the total displacements also includes the pre-deformation of soil nodes, but even then it is not logical. The figure below shows a discontinuity as indicated with the blue arrow which is unexplainable. At this point there is a vertical plate applied in the previous phase, but the soil on both sides are allready excavated in previous phases. So what is the meaning of the total displacement of a plate, and why is this not equal to the phase displacement for the first phase in which the plate is applied?
With the fixed issue [377180] according to the v23 release notes I expected that the total displacements of a plate would not include any displacements of the soil that occured before the plate was applied. But this seems not the case. I don't see a difference in this between v22 and v23.
Dear Hans,
As the fixed issue mentions: the Phase displacements used to contain the predeformation of the nodes, but now in version 2023 the Phase displacement no longer contain the predeformation. However, the Total displacements still does contain the predeformation.Hence, in version 2022 the Phase displacement was equal to the Total displacement, both containing the predeformation. In version 2023 the Phase displacement no longer contains the predeformation.
So if you're interested in the plate displacement, it would be better to check the Sum Phase displacements rather than the Total displacements.
With kind regards,
Dennis Waterman
Answer Verified By: Hans Breen
I don't see the difference between Plaxis V21 (figure below left) and V23 (figure below left). These are the results for the same model for the phases in which the plate is just installed.
The fixed issue solves the predeformation caused by soil nodes that were active before the plate became active. It seems that here there are no preactivated soil nodes - the horizontal plate is connected to another plate that is also not connected to active soil nodes. In which case this situation does not fall under the fixed issue and there will indeed be no difference between V23 and previous versions.