Problem description

Node-to-node anchors and fixed-end anchors are directly connected to structural elements (plates, beams, embedded beams) at the location of their connection. However, in PLAXIS 3D 2018  when:

1. you prestress a node-to-node anchor or fixed-end anchor
2. and you connect this anchor or fixed-end anchor with a plate element that has interfaces around it, or where two plate elements connect

that the structural connection between the anchor and the plate in this prestressing phase is not always properly applied. This results in wrong force transfer from the prestressed anchor to the plate element, and consequently might lead to incorrect deformations due to missing force connection of the anchor’s prestressing.

Note that this issue happens only during a prestressing phase in PLAXIS 3D 2018. In the case the anchor is not prestressed, the connection between the active plate and active anchor works as you would expect it to be.
The issue is resolved for PLAXIS 3D CONNECT Edition V20

Solution

This issue is now solved with PLAXIS 3D CONNECT Edition V20!

Whenever you use this prestressed anchor connected to plate elements in PLAXIS 3D 2018.01, please make sure to check the force transfer between anchor and plate and verify that it is properly connected during this prestress phase.