I'm seeking advice on how to handle the energy-dissipating steel bars in my model, where these bars connect to the longitudinal rebars at both ends to transfer force flow. I've been stuck on two main issues for a long time:

1. If the upper and lower longitudinal rebars are extended to connect with the energy-dissipating bars, severe numerical singularity warnings appear.
2. If the upper and lower longitudinal rebars are cut flush with the concrete edge (no extension) and the energy-dissipating bars are directly connected to them, over-constraint issues are reported.

Note that the upper and lower longitudinal rebar cages are embedded in the concrete, as required. This problem has been bothering me for a long time, and I'd really appreciate some expert guidance. I'm planning to post this on relevant international engineering/FEA communities for help.