Engineering Manual for Stepup Scaffold Walk Through Frames

[KootK]

I've got a good contractor client that I'm trying to help with a little construction engineering. Unfortunately, I've been unable to get my hands on the engineering data that I need for the projects involved. I've called and emailed the supplier repeatedly but, as is often the case, they don't seem to give me the time of day because I'm not an actual scaffold supplier. Anybody out there in the digiverse got a copy of Stepup's engineering manual?

]

 

[bridgebuster]

KootK,

I don't have the catalog but attached is some info I got from the NYC Building Department on sidewalk sheds. There are some dimensions in it.

 

[WinelandV]

It always boggles my mind that the very information that would make the product more usable is hidden away behind layers and layers of salesmen. Can your contractor friend call one of the distributors/suppliers and request it? Maybe add a veiled threat of "if I can't get ahold of this, I'll have to go with Aluma Systems (or whoever your preferred scaffold manufacturer is) because they will provide me with this info."

 

[Huevo]

This one?

 

[WinelandV]

Digging the test results, and photos of the test results at the end of that doc, Huevo. Certainly a bit unorthodox from what I'm used to seeing from scaffold providers, but should be able to get the job moving forward with it (IMO, caveat of not knowing exactly what KootK needs from StepUp).

 

[KootK]

This one?

Yessir... Canadian no less. Thanks so much.

IMO, caveat of not knowing exactly what KootK needs from StepUp

It's something like the scaffold shown below against the building shown below so that the mason's can do their thing. I'm presently on the fence as to whether or not I'll take this on owing to my lack of familiarity with the system. My past scaffolding work has all been reviewing drawings prepared by others which simplifies things considerably. Outstanding questions that I still have:

1) What form does the tie-back system take that connects the scaffold to the CFM wall?

2) This is a heat and hoard situation where the scaffold will be enclosed with insulating blankets. So there will be lateral loads. Unfortunately, the supplier literature doesn't speak to lateral loads which, frankly, seems a bit strange for what are essentially moment frames. How does one handle this? Analyze the frames on my own? Just assume reasonable tie-back spacing takes care of the lateral?

 

[KootK]

It always boggles my mind that the very information that would make the product more usable is hidden away behind layers and layers of salesmen.

If you call their stupid 1-888-STEPUP1 number, it puts you into an finite loop of vacation sales BS. Their willingness to annoy and frustrate the people wanting to work with their products is mind boggling. I guess service is irrelevant when price point is your only sales driver. We should all take this as evidence for why we should not allow ourselves to become commodities.

 

[TLHS]

It sounds like you've got a good relationship with the contractor. Can you ask what they'd normally see for tie backs? If they're okay with tying off at every scaffold level and that's what they're used to seeing, then I'd probably consider lateral strength of the scaffold assembly fine by inspection at a building height like this and concentrate on anchorage design.

 

[Brad805]

I am not familiar with this breed of scaffolding, but the ones we have looked at have accessories such as cross clamps to tie them back to the building structure. I seem to recall a spec for the maximum spacing for tie backs the last time I helped out a contractor. We used Metaltech scaffolding the last time (

https://www.metaltech.co/).

Maybe there is something useful to refer to. The typical frame is quite standard based on what I looked at.

The important thing to figure out is how they plan to attach the tarp at the roof level. A typical detail is to nail a 2x4 on flat to a 2x4 rail along the long side of the scaffold. The first time I did this they had used nails, and that did not calc out when you are dealing with 10'-0" spacings.

The attachment of the tarp to the scaffolding I have seen is quite simple. They do not want to cut holes in the tarps as most of the time they are rented. We have used u bolts to attach 2x4 strapping to the uprights, and then they usually wire the tarps to the 2x4 using the eyelets.

 

[jjl317]

Some thoughts from a former scaffold engineer -

Often scaffold ties are push-pull, with either a 2x4 or 2" nominal pipe compression member, paired with a tie wire tension element. In the States, for unenclosed scaffolds, OSHA 1926 has a number of prescriptive minimum guidelines for laterally tying the scaffold (methods, spacing etc.), but for enclosed scaffolds, the criteria basically just states to ensure it can withstand the imposed lateral loads.

In terms of technical data on frame scaffolds, I am unaware of any manufacturer who provides any information on how the frames might resist lateral loads (though I have been out of the business for awhile). In my experiences, enclosed exterior scaffolds designs largely glossed over the frame analysis and focused on the ties and enclosure material only. And in some cases, I believe that the enclosure material was designed to "break away" under certain wind criteria, with the use of clips that snapped over the frame legs. Another trick at dealing with the wind loads is to prevent workers from using the system when winds reach a certain threshold. Often, the tie back design was created with input the scaffold erectors, though I do remember at least one project where the enclosed system blew over (contractor enclosed after we had erected the system, without our knowledge).

From the analysis perspective, systems scaffolds (independent vertical legs and horizontals with end fittings) can be much easier to address (often with better technical information), but they are typically more expensive, and take longer to install.

 

[Lomarandil]

I'd also try as TLHS suggests. Depending on what you're anchoring to, the tieback capacity may make required spacing that tight anyway. It always drove my scaffolding designs.

Breakaway tarps and working restrictions (30-40mph wind was a common threshold, on some projects we would push for 20mph) are definitely common countermeasures.

----
just call me Lo.

 

[WinelandV]

Well... There was a clip-ring axial load test done (I believe in tension only), but you could use the 4:1 FS on those results to start determining what your spacing might be. How long will the scaffolding be up for? Using the ASCE 37, you may be able to reduce the wind load enough to show that you can get enough lateral support in to maintain usage for most days, even above 40 mph (assuming the blankets can handle the higher winds). Of course, you'll probably get push back on where you can even locate the laterals as the contractor needs to be able to do the work...

Sounds like there's a lot of back and forth with the contractor in your future.