expanding an opening on existing tilt up panel
expanding an opening on existing tilt up panel
(OP)
I need to cut an opening on an existing tilt up panel. There's already a 9' door opening but they want a 20'x20' door so we need to make that opening bigger. We have no information about the panels (no size, thickness or rebar info). Given the size of the new opening I want to frame it. I need some guidance on how to do this, does the framing goes around/inside the opening? Does it go outside (to the inside of the building, attached to the panels)? See sketches attached. thanks






RE: expanding an opening on existing tilt up panel
Have you established whether the tilt ups are load bearing? If so, are they stability elements (i.e shear walls)?
If they are simply facade elements, or even just vertical load bearing panels, a steel lintel frame around the inside of the cut opening could be used to transfer the load.
You need to have an engineered solution though. I would start by establishing the relationship of the panels with the building structure. You can then then find out other properties such as reinforcement, concrete strength using various non destructive testing.
RE: expanding an opening on existing tilt up panel
Usually the new tube sections extend from the floor slab to or very near the roof diaphragm.
Looks like you will be cutting a lot of vertical steel at the panel edges, as well as lintel steel.
Mike McCann, PE, SE (WA)
RE: expanding an opening on existing tilt up panel
Your sketch shows that you will leave one panel fragment levitated in the air by something and that fragment will have minimal edge distance to a large opening in the fragment. Much like a guillotine blade.
This looks like a disaster in the making.
RE: expanding an opening on existing tilt up panel
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.