Shell in Solid

Hello everyone,

For my model, I need a part of the shell to protrude into the solid for coupling to dissipate energy for the shell, for which I added the *CONSTRAINED_LAGRANGE_IN_SOLID keyword. But is the calculated acceleration not much different from the acceleration applied to the shell boundary by SPC? How to solve this problem? Is there a problem with the coupling method between my shell and the solid?

Thanks in advance!