The links that ishvaaag and I presented above are for soil nail walls, not tiedback walls. If you have a tiedback wall, then the tieback anchors are almost always attached directly to the soldier beams, whether thay are steel beams, drilled shafts, or secant piles. In that case, the wall facing is attached to the soldier beams, not to the tieback anchor heads. For steel soldier beams, the facing (whether cast-in-place or shotcreted) is attached to the soldier beams with welded, headed, tension studs. If using concrete drilled shafts or secant piles, the facing can be attached with rebar dowels.