Problem description

When a new phase is introduced in a calculation, its pore pressure calculation type currently is taken by default from the previous phase in the phase list instead from its parent phase. This should not be the expected behaviour.

The correct inheritance behaviour should copy the pore pressure calculation type from parent phases to child phases, regardless of the phase positions in the calculation’s phase list

Example

In the example illustrated below:

• <Phase 3> was added and then <Phase 1> was set as the start from phase
• it can be seen that <Phase 3> has <Phase 1> as parent phase, whereas the pore pressure calculation type (“Pore pressure” column) is taken from <Phase 2> instead being taken as “Phreatic” from <Phase 1>.

Solution

Despite that the current implementation might make it impossible to change the pore pressure calculation type after a re-parenting (change the phase it starts from), it is possible to correct this by an easy workaround.

This implementation will not present any inconveniences in some of the cases:

• For Plastic / Plastic drained / Consolidation phases with staged construction it will be solved automatically after the staged construction definition when pressing the Update button.
• For Safety and Dynamic calculations the pore pressures are taken by default from the phase it starts from, even though the pore pressure calculation type in the phase list might indicate a different calculation type.

Unfortunately this issue will affect these phase types:

• Plastic and Consolidation calculations with total or incremental multipliers
• and Consolidation phases using minimum excess pore pressure or degree of consolidation

In order to solve the possible inconveniences resulting from this issue, please use the steps as explained below:

• For the affected cases mentioned above, it is recommended to add the phase immediately after its parent phase by inserting this phase in the correct location.
• In the case of not being able to avoid this issue, it is recommended to insert a (Plastic) nil-step just prior to the troublesome phase, correcting the pore pressure calculation type and so solving the problem.