Any structural engineers in the house?

[bud buddah]

I'm working with the Sundial project (see the topic elsewhere in this forum) and we need some help with structural design. Is anyone in the bay area on this list willing to help out with some design work? If so, please contact me or Paul on the sundial discussion,
Thanks,
Jason

[Isotopia]

You might start by including dimensions/weights/materials/size/costs, etc.

A generally lame solicitation for help on a... ambiguous project more often than not results in no responses other than tittering and ridicule.

Cowboy the fuck up and provide some specifics - hippie.

[thisisthatwhichis]

Sorry ISO, but there is a thread on this....... Mwahhhh....

It should be included in the OP's post, I agree.......... And yea, he/shes still a f**in hippy.......

http://eplaya.burningman.org/viewtopic.php?t=38065

[bud buddah]

Iso,

All the specifics are at:
www.foggdesignmfg.com

You gonna "cowboy up" and do some number crunching for us?

Jason

[Bob]

Ditto what Iso said, but I'd also suggest you first try to contact others who've recently built tall crap at Burning Man and ask who they've consulted, if anyone.

[bud buddah]

Bob,
I was just thinking that I ought to get in touch with folks who built big stuff last year, and ask how they handled this. The minaret at center camp might be a good place to start. But I suspect that since it was all steel, he didn't worry too much about loads. We have a suspended platform which makes for a tricky design.
Jason

[Bob]

One thing I notice from your pics -- it's not apparent how you plan on anchoring this thing to the ground to prevent toppling over due to wind or climbing loads, or how the main pole is stabilized.

[TomServo]

One thing I notice from your pics -- it's not apparent how you plan on anchoring this thing to the ground to prevent toppling over due to wind or climbing loads, or how the main pole is stabilized.

Thats why we're asking for someone who knows engineering. The way the project stands now, is anchored by its weight and Base structure alone. Looking at the models, the center beam, that extends below the legs, could possibly buried. Also, are questions regarding weight loads on the platform. Its creator has detailed "blueprints" of the structure, that he can provide.

[TomServo]

Ditto what Iso said, but I'd also suggest you first try to contact others who've recently built tall crap at Burning Man and ask who they've consulted, if anyone.

and yes, I believe I mentioned that to the designer...and is probably whats happening.

[Stickygreen]

I'm no engineer, so I can't help you with number crunching, but the assumption that the thing will weigh itself down to the ground is dangerous. The largest structure I have been involved with on playa is the roots society's dome's. they are much heavier than your project and they are anchored down by at least 2 sPikes at each intersection that meets at the ground. These ground sPikes are fairly large, probably about 3' long, we used an air powered jack hammer to drive them in. Can't remember how many total spikes there were, but it was more than 100.

You really need to anchor this thing down, like fort knocks.

[TomServo]

The base of this project is quite large, and spread out...I think it would take a massive windgust to topple the sun dial. If my homemade canopy can withstand 100mph plus winds, I think this piece will be fine. Although additional anchoring might set some minds at ease.

[capjbadger]

The base of this project is quite large, and spread out...I think it would take a massive windgust to topple the sun dial.

Well then you've come to the right place!

-Badger

[Dustdevil]

Sometimes an engineer can spot something you didn't think of. When I designed the pipeline for Crude Awakening I took my drawings to a mechanical engineer for approval. I actually got him to put his mark on the final prints. It was an extremely expensive process.

He approved most of what he saw. He changed the specs on the welding rod we were using and he was able to run the NFPA formula for heat/time
and distance and gave us a safe perimeter measurement.

He found one thing I never thought about. The pipeline was elevated at such an angle as to create a 2% grade towards the tower. It was held in place by tressels we made. I did not have enough support. He looked up to see the highest winds recorded on the Playa and the prevailing direction and the direction of the pipeline. We had to double the number of supports. His concern was the pipeline could begin to occillate in high winds.
The winds came up while we were elevating the completed pipeline and it did begin to occillate. It was a little scary because still had to do the hydrostatic test.
This engineer was worth every penny we paid him.

[skibear]

I'm an electrical one. Ill remove your shorts.

[TomServo]

The base of this project is quite large, and spread out...I think it would take a massive windgust to topple the sun dial.

Well then you've come to the right place! ;)

-Badger

Yes I know! Been through some pretty heavy winds over the past 12 or so years on the playa. The base is quite a bit wider than the standing platform...If anything, I think it would shift..rather than tip over...and thats a big IF. I think the main concern is weight on the platform...although I think it should be secured somehow.

[TomServo]

@Dustdevil- I remember Crude Awakening. What was the wind load like on bare timber? The highest part on this project is a single piece of wood, with a metal framed top. Not wide at all, and a small target for wind.

[Bob]

Well, fuck, what could *possibly* go wrong if you don't anticipate dynamic loads instead of just a bunch of meek hippie static loads on the deck? Everybody is asked to anchor their fucking structures. Anchor your fucking structure. Stuff blows over on the playa. Maybe you need to talk to a rigger or carpenter, not an engineer.

[TomServo]

Well, fuck, what could *possibly* go wrong if you don't anticipate dynamic loads instead of just a bunch of meek hippie static loads on the deck? Everybody is asked to anchor their fucking structures. Anchor your fucking structure. Stuff blows over on the playa. Maybe you need to talk to a rigger or carpenter, not an engineer.

shut up. Your snark is getting old! Or does that give you a sense of relevance?

[Dustdevil]

I no longer remember the figures for the load on the Oil Derrick. We did use cables and huge concrete cubes that each leg of the tower was attached to. In the strongest wind there was absolutely no swaying of the tower. The structure was designed to hold 200 people on the platform and another 200 people on the stairs. The structure weighed in at 54,000 pounds.

[TomServo]

I no longer remember the figures for the load on the Oil Derrick. We did use cables and huge concrete cubes that each leg of the tower was attached to. In the strongest wind there was absolutely no swaying of the tower. The structure was designed to hold 200 people on the platform and another 200 people on the stairs. The structure weighed in at 54,000 pounds.

Thanx, this structure wont hold nearly as many people. It's very narrow, and the spots that would catch wind are towards the bottom. Its not my project, but volunteered to help build it. I fell in love with the sun dial, when I first saw the pic. The designer is a noob, and Ive never been a part of building tall structures at Burning Man.

[Bob]

Like I said, talk to a pro, and good luck with that attitude. Hope you don't want an engineer or whomever just to bolster your own ego.

The website, renderings and photos don't show what you're using for connections, so there's no way to judge what's holding the thing together, regardless of what's pinning it to the ground to prevent it from translating horizontally or toppling over. In my experience, the first thing the org looks at is some king of anchoring, so you might want to pay some attention to that. Or not. It's been a few years since I've reviewed structures for the org, maybe they don't give a shit about cock-eyed paperweights anymore.

[Dustdevil]

Bob makes a good point. In CA we used huge steel knuckles that were fabricated and drilled at American Steel to connect the stress bearing joints. And I can assure you, the anchoring and strength of the structure will be looked at before you begin building it on the Playa.

[TomServo]

Like I said, talk to a pro, and good luck with that attitude. Hope you don't want an engineer or whomever just to bolster your own ego.

The website, renderings and photos don't show what you're using for connections, so there's no way to judge what's holding the thing together, regardless of what's pinning it to the ground to prevent it from translating horizontally or toppling over. In my experience, the first thing the org looks at is some king of anchoring, so you might want to pay some attention to that. Or not. It's been a few years since I've reviewed structures for the org, maybe they don't give a shit about cock-eyed paperweights anymore.

Luckily, the designer is more level headed than me. My ego is in check Bob. Is yours?
I think an engineer has volunteered to look at the blueprints. Next is the whole insurace question...mentioned on another thread.

[bud buddah]

Dustdevil,
Where the large concrete blocks something you trucked out there? Do you recall roughly how big they were? I suppose we'll just have to do some math to estimate how large a weight we'll need on the end of each leg to keep this thing from moving if 20 people jump up and down on one edge of the platform.

[Dustdevil]

They were about 2.5 to 3' cubed. They were poured in Oakland and brought out by truck.