Material specification of round soldier piles

[milkshakelake]

How do you specify the material of round soldier piles? I'm speaking to a soldier pile supplier. They explained:

1. Prime Pipe is made using API 5CT specification, which has strict mechanical and chemical properties.
2. Some stuff isn't good enough for that. This is called Mill Secondary Material. That's what soldier piles are made of. Thus, they don't have a material classification.
3. They ship with material testing reports attesting to their yield strength, usually 80 ksi or more. This is the main thing that designers need.

I agree with them that I only care about the ksi when it comes to soldier piles, or really any type of steel. The problem is that an official with authority is rejecting my drawings calling for soldier piles to have minimum 80 ksi design strength. He's saying that there needs to be a material specification attached to it.

Is there any code I can use that says that I don't need to specify the material of a soldier pile, only its strength?


The closest I can get is from my local code based on IBC, which doesn't help:

2203.1 Identification. Identification of structural steel elements shall be in accordance with the requirements contained in AISC 303. [...] Other steel furnished for structural load-carrying purposes shall be properly identified for conformity to the ordered grade in accordance with the specified ASTM standard or other specification and the provisions of this chapter. Where the steel grade is not readily identifiable from marking and test records, the steel shall be tested to determine conformity to such standards.

 

[LittleWheels]

When I think of soldier piles, I usually think of small retaining walls with steel H-sections and timber planks. In my world, using tubular piles mostly defaults to king pile walls with sheet piling retaining soil between the tubular piles, generally with much larger dimensions (e.g. ports and harbour work). Our tubular pile specifications have various requirements (e.g. weldability, impact) that go beyond just the yield strength.

What sort of scale are we talking about here?

 

[milkshakelake]

It's not at the scale that you mentioned, with sheet piles and king piles. It's around 14' deep excavation, using something like 9.625"x0.5" micropile casing (similar to round HSS) that will be embedded another 20' or so into the soil. They're spaced at 6' on center with wood lagging in between. It's basically a cantilever retaining wall.

H-piles or W-piles are much simpler because they have simple ASTM material classifications.

Since you mentioned weldability, that might actually be a concern, because we need to be able to weld rebar to it. Though impact isn't a concern.

 

[MTNClimber]

There is no code that I'm aware of requiring a specific yield strength of micropiles used in micropile and lagging walls, just a minimum per AISC. The supplier can provide the micropile casing with testing reports showing a minimum of 80ksi, which is typical of micropile casing. The authority wants a minimum of 80 ksi. So, what's the issue of requiring 80 ksi to be shipped to the site? Specify and be done with it.

You can, and will likely need to, weld to the micropile casing for an angle or threaded rod with a steel plate to hold the lagging boards.

 

[milkshakelake]

@MTNClimber My requirement is 80 ksi, and I have testing reports showing it to be 111 ksi. The problem is that the authority wants a material specification on it. As in, ASTM or API spec of some kind. But since the micropile casing is mill secondary material, it doesn't actually conform to any standard at all.

 

[LittleWheels]

Don't you just need to write a project-specific material specification for this material? Micropile casing shall have minimum 80 ksi yield and weldability shall conform to etc. etc.

I very rarely use American standards, so I may be talking out of my <choose your own>

 

[milkshakelake]

Thanks LittleWheels! I didn't think of writing my own spec. I'll just do that.