Problem

SACS indicates the following error when I tried to create the spring in SACS:

 

Please advise how to rectify the errors.

Solution

This error is usually associated with a mismatch between the PLAXIS mesh and the SACS mesh of the suction bucket wall. Basically, the SACS Suction Bucket program cannot locate a node in the SACS model on the PLAXIS mesh.

In PLAXIS-SACS interop, SACS imports soil stresses/pressures at the (negative and positive) interfaces between suction bucket walls and the soil. Therefore, user must ensure the PLAXIS interfaces cover the entire length of the suction buckets by default. 

For example,

a PLAXIS model with the soil top elevation is -36.62 m, while the suction bucket top elevation is -36.52 m. It means the suction buckets are 10 cm above the soil. As a result, this portion of the suction bucket doesn't have any soil-bucket interface - leading to this error.

The reason for this difference is because user is using the "create fictitious borehole" option (see screenshot below) while importing the suction bucket model. This option was implemented to create a soil profile quickly for testing purposes. 

We recommend unchecking this option, manually entering the soil borehole elevation and properties, and then re-creating meshing and running the analysis. It will most likely fix the user's issue.