Strategy Needed For Modeling Foundation Condition

[Richard_Morrison]

I am trying to figure out if modeling this condition is even possible in Chief so that live sections approximate reality, rather than drawing a CAD "whiteout" detail". I haven't come up with a good way to do this, yet, so I thought I'd toss this out there to see if anyone has any ideas. Basically, I'm trying to draw roughly the attached condition. A new foundation under an existing foundation, with split levels. Major problem is that two foundation walls are not happy occupying same space at same time.

[DRAWZILLA]

Of course anything can be done, but I don't think you can do it automatically, I think you would need to do it with p-solids or a molding p-line with multiple moldings and maybe some cad work to get the plan view correct.

[Bill_Emery]

I'd start out with a pony wall, and then provide the tapered footing with a 3D molding poly line the same shape as the old footing. A lot depends on what you want to show in plan. The section and 3D don't look too difficult.

[mthd97]

Training video 1573 will give you the strategy using foundation wall tools to do the job for you and also you will need slab and or polyline solid tools as well.

In other CAD you need to be a master of the 3d profiler tools, I have seen it done in 3d but I need to brush up on that skill myself.

All the best.

[Greg_NY61]

I never seen underpinning being done this way. 

[Richard_Morrison]

Thanks, all. Pretty much what I expected, and this may not be the right program to do this particular project in. I will play around a little more, but I'm ready to bail. (To mthd97, it's really a matter of doing a complex wall profile in "OtherCAD" (actually ArchiCAD, which will not be mentioned here), not the Profiler tool. After that, it works just like any other wall. Well, probably would be two walls for more flexibility.)

 

This is, of course, not really the way the underpinning will be done. (Full height side foundation wall with footings extending underneath existing footings on 4' centers.)  I just threw a sketch in here to get the concept across of a new foundation under an existing.

[VHampton]

HI Richard,

 

Why not draw the wall conventionally and then add either a molding poly-line or a poly-line solid to show the existing portion?

 

The contractor must have one of the Ancient Aliens levitating gizmos on site to make the new pour go ok, but let's not get into that.

[mthd97]

Thanks, all. Pretty much what I expected, and this may not be the right program to do this particular project in. I will play around a little more, but I'm ready to bail. (To mthd97, it's really a matter of doing a complex wall profile in "OtherCAD" (actually ArchiCAD, which will not be mentioned here), not the Profiler tool. After that, it works just like any other wall. Well, probably would be two walls for more flexibility.)

This is, of course, not really the way the underpinning will be done. (Full height side foundation wall with footings extending underneath existing footings on 4' centers.) I just threw a sketch in here to get the concept across of a new foundation under an existing.

I would not like my chances of butting two foundation wall types up against each other in Chief Architect unless you can convert the monoslab produced by one of the foundation wall types into a polyline solid that will not interact with the other foundation wall tool producing the pier and beam footing in CA.

Also regards otherCAD I would use the complex wall profiler tool for the pier and beam type set up on the external wall and then create a mono slab from the slab tool with the profile on your detail so they do not interact with each other. I am not sure but I think the complex wall profiler will also work on slabs as well in other CAD if I am not mistaken?

We still have a 3d profiler in ArchiCAD from the old days that was designed to do a similar job as a cadimage add on tool now (used to be a goody tool once upon a time down under before AC V10)

I think it can be done in both programs with a good advanced user?

Keep us posted as to what worked best for you?

I would use other cad becuase of that funny shape in the external P&B footing wall and I would not like my chances of bending it around a corner if the case need be. OTH you could punch a hole in a polyline solid to get that shape to go around a corner but that just gets messy and too time consuming for me.

[Richard_Morrison]

I can see that a lot of you didn't like my fictitious detail that relied on the levitating gizmo. (Silly Earthlings...)  Should have taken the time to do something more realistic, I guess, which I now have done. The "real" detail is going to be similar to the revised detail that is now in Post #1. Modeling problem is the same, though. I've decided that sometimes it's best to use the best tool for the job, and maybe sometimes it isn't Chief. Foundations are getting better at every release, but still need to be improved for remodeling conditions.

[mthd97]

I would have suggested that you would not need a pier footing just the monoslab designed to carry the external concrete wall a bit like we build cellars down under with sarter bars coming out of the edge beam of the monoslab for the external pier or wall or whatever the case is. Done in one pour, less concrete, less labour. I was looking at it from a builders perpective but I did not have all the details and what it would really look like in 3d.

I would do the same only becuase of that rhombus shape in the pier or side wall otherwise I would use Chief if I could make the changes that I just mentioned above as well.

All the best.

[DRAWZILLA]

You can also use the "Auto detail tool" in section view and it will give you a p-line applied right over the foundation. You can then manipulate that p-line to get exactly what you need to show, but the 3d model and materials list won't be correct. I do this all the time when I can't get the foundation to show correctly in section view.

[mthd97]

From those new details above, that is the realistic way to do it. I did not pick up the existing rhombus footing from your first sketch.

Now if we could edit a cross section of a footing from rectangle to rhombus in the cross section window and the 3d model was changed, that would be good for CA?

I would use cadimage slab edge in AC if I needed extra tools to edit the monos slab footing to get that shape in your detail above from the cross section in AC.