Here is an example project that shows how to model typical MSE Walls in TBC. With the latest TBC tools there may be better ways today of doing some of the steps but the keys to success are here for sure.
Exercise 24 - Corridors - MSE Wall Footing Example.7z (804.6 KB)
The enclosed Powerpoint Slides in slides 21 - 24 show some details of the way to think through this problem
CEC-1434 Sharp-CA.pptx (569.6 KB)
The Video below shows the technique to use to compute the Strap Depths using the variable wall height in corridor instructions.