Foundation for a bronze statue 1

[archeng59]

A client purchased a large bronze statue and needs a foundation. Unfortunately, the sculptor provided no means of anchoring the statue to a base and will not help in any way. I can design the footing easy enough, but anchoring the statue to the footing is puzzling. The statue is hollow. I can cut holes in the statue, place vertical dowels in the statue, grout bars into the hollow voids and then braze bronze plates to cover the holes. I am concerned about damaging the statue during the hole cutting and brazing process. Also, concerned that the grouted voids will not provide the stability needed. This is a first for me. Anyone do this type of thing before? Any recommendations?

 

[JAE]

Can you weld some kind of bronze dowels to the bottom and epoxy them into the footing?

 

[archeng59]

That might be an option. The contractor is trying to find a person experienced in brazing bronze. When/if he does, we will talk to that person about options like that one.

 

[TehMightyEngineer]

Does the statue need to resist uplift? I would assume you're just worried about lateral loads correct?

EIT with BS in Civil/Structural engineering.

 

[msquared48]

If this statue is of a person, you could always cast the statue up to the knees in concrete and claim the Mafia did it.

Mike McCann
MMC Engineering

 

[archeng59]

There will be uplift due to the lateral loads and due to someone hanging off the front of the statue.

 

[msquared48]

Yea, but again, you can blame that on the Mafia.

Mike McCann
MMC Engineering

 

[archeng59]

The contractor suggested burying the statue in concrete and saying it's stuck in the mud. LOL. Maybe you all are on to something there.

 

[TehMightyEngineer]

Another question, how big is a large bronze statue? Are we talking like a 6' tall, few hundred pound statue?

EIT with BS in Civil/Structural engineering.

 

[SkiisAndBikes]

I have seen 1-1/2" diameter stainless steel dowels welded into the base of bronze sculptures. There is a specific process for welding the stainless steel to bronze, a welding specialist should be able to provide this information. There may need to be an internal network of stiffeners added to the sculpture to adequately support the dowels. Welding bronze to bronze should not be a problem, it's done all the time. Using templates of the dowel locations, holes can be drilled into the concrete base, checked to ensure alignment, cleaned and then filled with epoxy. As you set the sculpture down onto the footing, I find setting the sculpture down on a bed of thin grout helps improve full contact between the base of the sculpture and the top of the concrete footing. Be aware that using this method makes removal of the sculpture for relocation and/or maintenance very difficult.

 

[archeng59]

The statue is approximately 12 feet tall and is a horse rearing on its hind legs.

 

[TehMightyEngineer]

What about welding a bronze base plate onto the hind legs and then anchoring that as a traditional base plate?

EIT with BS in Civil/Structural engineering.

 

[msquared48]

Now this seems to be a horse of a different color here.

Where is the CG in relation to the rear legs? Sounds like there could be a lot of moment here. Did the artist install any special reinforcing into the statue to resist this moment, even to the extent of casting the legs solid?

I assume you are responsible only for the foundation design and not the structural integrity of the statue.

I'm still working on the Mafia issue here.

Mike McCann
MMC Engineering

 

[cvg]

tell the artist you are going to saw the statue in half to assist in installing the interior reinforcing and then weld it back together. Then maybe he will offer a little help.

 

[TehMightyEngineer]

All the bronze statues that I've seen that you described are like this:

http://thebronzesculptures.com/bronzesculptures/images/lgbrz06horse1943.jp

With a large bronze "footing" that gets anchored into a granite or concrete block. Is this the hollow section that you describe? If so, I would do as you said but rather than grouting into the voids (which I agree would have a questionable strength) bolt them down to the statue in some way.

Also, I second msquared48's comment that the horse will put some serious moments on any anchors but I imagine you already realized this given your mention of people hanging off the front.

EIT with BS in Civil/Structural engineering.

 

[Teguci]

Chop off the bronze horses head and put it in the Owner's bed

 

[archeng59]

Unfortunately, the sculptor did not provide anything in the bronze casting for anchoring purposes. The statue has a large bronze base, but it is very thin. In my opinion, the anchor points need to be at the legs somehow. It's the "somehow" that has me stumped for the moment.

 

[msquared48]

True. If the moment is too great, the horse will just have stumps.

Mike McCann
MMC Engineering

 

[TehMightyEngineer]

What about welding a thickening plate to the bronze 'baseplate' and bolting through that?

EIT with BS in Civil/Structural engineering.

 

[dinjin]

Can you post a picture and see if some type of
wood structure could be built inside made of
4 x 4s? Have two guy wires inside and turn the
statue until the guy wires become tight by twisting
inside and anchored in the footing?