OT: Steel deck - seeking advice/idea

[Rex]

Update

The method I ended up with is "none of the above". I am building out from one corner, counting holes and using levels to keep everything in the same plane. I expect it will introduce some error over the 40-ft length. So far so good.

[boats]

Plain optical Transit and rod is the way I have always laid out a job. This after working one summer on a USCE Hydrographic Survey party 50 years ago. Makes me a 3 month expert. We set tide gauges and laid out dredging lines off USGS benchmarks.

Disadvantage to the level and rod it’s a two man job. Instrument man and rod man. That’s about the only disadvantage. Set the transit on a corner you can shoot the elevations and angles for all the post etc. level will do the elevation not the angles. Either one inexpensive rentals.

Boats

[QSIMDO]

You're not that high, build stone or block walls, back fill and lay down pavers.
Job done.

[Rex]

Late note. A green laser level can be seen. A little expensive but, solves the problem.

Good idea. This popped up https://www.aliexpress.com/item/5-Li...B&gclsrc=aw.ds

Something like this might be adequate https://www.amazon.com/Cross-Line-La...en+laser+level

[Mike Amick]

Late note. A green laser level can be seen. A little expensive but, solves the problem.

[Rex]

Thank you for that. I may still need an engineer to interpret it and apply it to my design.

By that table, the load-bearing capacity of the column increases by sliding the next small cross-section inside. I don't have any 2.25 to do that, but I can bolt two together - "sister" them. I think that would accomplish almost the same increase in load capacity - double?

[Rex]

If you set the posts on a stable rock or concrete footing (block) and brace them can you do away with digging post holes. I would think the weight and bracing would hold it in place OK.

You are probably right. The framework is going to weigh around 4000 lbs, without the decking, so it isn't going to blow away. Plus, the hot tub will somewhat anchor it in place.
The tallest edge is also on the softest ground, though still heavy with rocks, so I am certainly going to use concrete footers in 2-ft deep holes there.
I'm thinking I'll pour footers where I can. Where the rock is too solid I'll place the post and pour a block around it and over the rock. I may drill the rock around that spot to promote adhesion.

[wdtom44]

If you set the posts on a stable rock or concrete footing (block) and brace them can you do away with digging post holes. I would think the weight and bracing would hold it in place OK.

[Rex]

Rex, some information regarding beam and column loading values as it applies to 10 and 12 gauge (both perforated and solid) telespar used in roadside sign installations. This should give you something to at least chew on rather than constructing a project without any idea of the strengths inherent to a key component of your project.

https://www.unistrutohio.com/wp-cont...oad-tables.pdf

Thank you for that. I may still need an engineer to interpret it and apply it to my design.

[Rex]

3 things come to mind:
1) Codes and inspection requirements
2) 2x2 Tubing used as a column is load limited due to buckling
3) The allowable span of the tubing may be quite limited

I'd contact a structural engineer or at least consult some engineering texts to give confidence the the deck will stay put especially if the concentrated load of a hot tub is planned. Just my $.02.............

1 - I am in the county, no codes or inspections
2 & 3 - I wonder how I can determine that? Wait, I just saw Willy's post!

The hot tub will be recessed and sitting on a poured concrete slab after the framework is up.

[BobinOK]

Old House video, line level, water level and laser level.

https://www.youtube.com/watch?v=YuK5d7zNRZw

[Willy]

Rex, some information regarding beam and column loading values as it applies to 10 and 12 gauge (both perforated and solid) telespar used in roadside sign installations. This should give you something to at least chew on rather than constructing a project without any idea of the strengths inherent to a key component of your project.

https://www.unistrutohio.com/wp-content/uploads/pdf/library/unistrut-telespar-load-tables.pdf

[BudB]

3 things come to mind:
1) Codes and inspection requirements
2) 2x2 Tubing used as a column is load limited due to buckling
3) The allowable span of the tubing may be quite limited

I'd contact a structural engineer or at least consult some engineering texts to give confidence the the deck will stay put especially if the concentrated load of a hot tub is planned. Just my $.02.............

[Lee Cordochorea]

I don't mind it being 1/2" out of level over the 40-ft length, I just want it straight.

Ground ain't going to stay put anyway, is it?

[Rex]

Those steel posts are called Telespar.

However whenever we got into several areas of our territory where we knew the ground was extremely boney we would not even think of using the standard sledge as this was almost guaranteed to be an exercise in futility. If one was fortunate enough to get a post in far enough the post was probably as buggered up as the guy swinging the sledge.
However we did have access to one truck in the fleet that was equipped with a hydraulic telespar driver. It resembled a large construction grade air jackhammer, although this one was as mentioned hydraulically driven. It was magic using this tool. In exactly the same spot where one was left sweating and driven to tears with a bent piece of telespar, that unit would pop a telespar anchor into the ground straight and unscathed.

I should clarify the above statement by saying that the long telespar posts are not driven into the ground by themselves.
A 3-4 ft. anchor, which is just telespar one size larger, is driven in first then the main section of telespar is dropped into it, much like a trailer hitch slides into a receiver, and then pinned into place using drive rivets like these.


Makes assembly very fast and all you need is a hammer to secure them and a punch to drive out the "bullet" if one needed to disassemble anything assembled using them.

Hope the info helps, see if you can rent one of the drivers if you go this route. Digging holes in rocky ground is no fun.
Good luck on your new fireproof deck!

Good info, Willy. I've never seen those posts installed. I'll probably want to use concrete footings for this application though.
I'll check into those rivets for sure. I intend to use short pieces of 2" to splice the 2.5"