What's the load capacity of 6 aluminium posts?

[MikeMarshall]

TL;DR Summary

Anyone know the load capacity of 6 aluminium boxes 150mm x 150mm 3mm thick wall and 2 metres in length?

Hello

First time here! I have acquired 6 aluminium boxes they are 2 metres in length, they are 150mm x 150mm square and the walls are 3mm thick (they are also powder coated).

My plan is to use all 6 boxes upright as posts for a covered pergola or in other words a fancy BBQ hut, so I will be putting a flat-ish roof either osb boards and rubber or some kind of pvc corrugated roofing. The posts will sit in post shoes that will be fixed with bolts and concrete.

My question is how much weight will I be able to load onto the posts? I will frame the posts with 47 X 120 joists and the finished structure will be 3 metres wide by 2.4 metres long. I need the weight bearing calculation to help me decide what roofing to use.

Thank you for any help!

mike

 

[berkeman]

Welcome to PF, Mike.

How windy is it where you are building this outdoor structure?

 

[MikeMarshall]

Welcome to PF, Mike.

How windy is it where you are building this outdoor structure?

Hello Berkeman, not very windy to be fair we are in Nottinghamshire.

 

[Dr.D]

Boxes were not designed to function as posts, so we might wonder about how the corners are constructed. Without a lot of detail about the boxes, very little can actually be said. In addition, this will be a structure 2 m off the ground, a potentially dangerous fall for people on the platform. You really need to speak to a local structural engineer for advice.

 

[MikeMarshall]

Boxes were not designed to function as posts, so we might wonder about how the corners are constructed. Without a lot of detail about the boxes, very little can actually be said. In addition, this will be a structure 2 m off the ground, a potentially dangerous fall for people on the platform. You really need to speak to a local structural engineer for advice.

Ooh Dr.D I think you might be over thinking! please follow link: https://www.tuin.co.uk/aluminium-post.html
Basically its aluminium posts - which are aluminium boxes designed to be used as posts. The corners will be bolted together like any pergola structure probably with bolts and also where we live people do not stand atop pergolas or bbq huts so no risk of falling.
Thank you for your time in replying but if i simplified the question it how much weight could 6 x 2m tall 150mm square with 3mm thick walls aluminium boxes/posts with stand?

 

[jrmichler]

There is more to building a pergola than merely holding up the roof. There are wind loads, snow loads, somebody tying a rope to the structure, and miscellaneous unexpected loads. For these reasons, plus legal liability, PhysicsForums does not do consulting engineering.

Therefore, this thread is closed.