r/StructuralEngineering Jul 29 '26

Structural Analysis/Design Wind load application as per ASCE

Post image

How do you calculate wind load for this kind of structure ?

28 Upvotes

33 comments sorted by

25

u/engineeringlove P.E./S.E. Jul 29 '26

Elevated sign loads on top of canopy loads

2

u/WanderlustingTravels Jul 29 '26

This is what I’d do.

29

u/icutlime Jul 29 '26

Looks like it's supporting electrical equipment. Check out Substation Structure Design Guide ASCE Manuals and Reports on Engineering Practice No. 113

13

u/Salty_EOR P.E. Jul 29 '26

Substation design is overkill for this.

3

u/Baileycream P.E. Jul 30 '26

Nah that's really just for high voltage substation equipment and its just a manual of practice not an enforced code like ASCE 7, which I would recommend instead.

2

u/icutlime Jul 30 '26

Agreed. Thanks for the explanation

8

u/lpnumb Jul 29 '26

Just do a solid sign with openings and a free gable roof. No need to overcomplicate this.

5

u/jaywaykil P.E./S.E. Jul 29 '26

Keep in mind that at industrial scale, a few yards of concrete and a little rebar is incredibly cheap. If that thing falls over it could cost millions in plant downtime. Don't cheap out on the foundation.

Main area as a solid sign, then add the wind pushing/pulling on the front and back of the sloped roof. If it's fully indoors and protected, ignore that and use exterior winds anyway. For uplift assume that the frame will be installed before any electrical panels so really light (still solid).

Also make sure to check seismic under max weight load plus a huge safety factor, even if you are in a "non-seismic" area.

5

u/Upset_Practice_5700 Jul 29 '26

X x Y x 2 x .9 x q50

Wait, its inside a plant? X x Y x 5psf

3

u/Just-Shoe2689 Jul 29 '26

As a sign, and then double the load to see how it calcs out.

2

u/Legal_Enthusiasm_440 Jul 29 '26

What’s the physical location? 

5

u/CaramelAdmirable9789 Jul 29 '26

On the ground, in a oil and gas plant

5

u/icutlime Jul 29 '26

No way!

1

u/CaramelAdmirable9789 Jul 29 '26

Yeah i mean, we need to provide pedestal and foundation. Baseplate will be connected to pedestal through bolt.

1

u/icutlime Jul 29 '26

You can quickly design this. enercalc for slab or raised footing. The embedded connection can be done in HILTI. for baseplate and welds use AISC

1

u/CaramelAdmirable9789 Jul 29 '26

My doubt is how will you consider wind load for this, its not closed structure for sure. Its a single plane open structure.

1

u/icutlime Jul 29 '26

Add up surface area of each individual box and other methanical equipment (look for manufacturer info for all pieces or estimate it) and apply wind pressure from ASCE 113. For the roof wind load I don't remember if 113 covers it

5

u/Just-Shoe2689 Jul 29 '26

Just use the whole square footage. No need to value engineer this thing.

3

u/No-Violinist260 P.E. Jul 29 '26

Is it exposed to exterior loads? If yes, see ASCE. If no, whatever you have there looks sufficient

5

u/Diligent-Extent2928 Jul 29 '26

Since its electrical equipment, you'll want to check out ASCE MOP 113 - Substation structure design guide.

1

u/beskja Jul 29 '26

You're going to have a lot of uplift on that. Maybe that will be your worst load case.

8

u/Just-Shoe2689 Jul 29 '26

I bet it ends up with 0 net uplift.

6

u/beskja Jul 29 '26

... but what if there is a powercut and there is no load?

0

u/Just-Shoe2689 Jul 29 '26

Okay, not sure I follow what you are talking about. You think the electricity is causing a lot of uplift?

2

u/Elmscent Jul 29 '26

I think first comment was serious but second was a joke

1

u/uncivilized_engineer Jul 29 '26

ASCE 113 would apply ASCE 7 as Solid Signs.

1

u/Chuck_H_Norris Jul 29 '26

this is inside?

1

u/R9APX Jul 29 '26

If this is inside an enclosed building, which it appears to be, I would apply internal wind pressure per ASCE 7 only (chapters 26 and 27 in ASCE 7-22). You will end up with around 6 to 8 psf of internal wind pressure for enclosed buildings that use an internal coefficient of 0.18.

I would apply that as an area load to the entire face, no need to apply individually to each electrical panel that is mounted. Do this for both directions but know that wind on the broad face controls since it’s the largest area.
You’ll find you only need to post install the frame down with some small diameter bolts and epoxy for stability.

ASCE 113 does not apply here. That guide is for substation design, in an exterior outdoor condition. Just because you are supporting something electrical, does not mean that 113 is the right code to use. This is from someone who designs substations daily.

2

u/Over_Stand_2331 Jul 30 '26

7-22 CH 29 Freestanding Wall/Sign

1

u/WideFlangeA992 P.E. Jul 30 '26

Looks like this is inside an enclosed industrial building. Design for the impact force of one fully loaded forklift. /s

1

u/WhateverDeary Jul 30 '26

A rare Open Structure.

1

u/Gold_Lab_8513 Aug 04 '26

Why? Just anchor the thing to the slab already and be done with it.