×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Cantilever Wind Canopy Design

Cantilever Wind Canopy Design

Cantilever Wind Canopy Design

(OP)
Hi All,

I am designing a canopy shade structure for a manufacturer to eventually be used in Florida and potentially other states. Its a 2 column design, the columns are spread 33ft apart with a cantilever shade extending about 11 ft out and with a curved fabric roof structure ranging from 6 degrees to 22 degrees. See attached for a simple diagram.

I conducted the components and cladding wind load calc and focusing on the uplift condition which would be controlling (D+0.6W ASD). With this the GCP for overhang perimeter is fairly high at -2.2. I am designing for a breakaway canopy system at 75mph so design wind speed at 105mph per Florida Building Code. I am ultimately getting 68 psf of uplift, which seems a bit high to me.

I have looked through the forum and ASCE 7-10 and cannot find a specific section that applies to these canopies. I am trying to value engineer it and my design seems to be a bit too conservative. Is there a reduction that I can consider that maybe I am overlooking? I do not think using the component & cladding procedure benefits me here. If I could use a field or even perimeter value for my GCP this would help, but technically I would say this should be an overhang.

Any suggestions would be appreciated! Thank you

RE: Cantilever Wind Canopy Design

(OP)
As a follow up, I found in ASCE 7-16 the section on attached canopies 30.11. I did not find this in ASCE 7-10. But I can use 7-16 since this product will be implements 6+ months I believe 7-16 will be adopted soon.

With this I found that using the criteria base speed of 105 mph,
Kz = 1.13 (at a max of 60 ft mean elevation height)
Kzt = 1 (staying conservative)
kd = 0.95 (circular curved roof)
ke= 1
qz = qh = 0.00256kzkztkdkeV^2 = +/- 30mph

Using the figure 30.11-1B with greater than 100 sft surface area
My GCpn = -1.13,+0.63

Resulting in -34.3, 19.1 psf

I am happy with this result, the only thing is that ASCE is using this for a "connected" structure not a stand alone, does anyone see an issue with this?

Thanks again!

RE: Cantilever Wind Canopy Design

I typically find canopy attached to building have stronger uplift than stand alone, so you are probably on the safe side. For reference I recently did a calculation for a canopy in Toronto using Eurocode (never saw ASCE 7-16 yet, and canadian code mentions nothing on canopy) just few weeks ago and got 1.4kPa uplift ~ 29psf overall.

There is a section in the ASCE 7-16 for open structure as well if that is closer to your condition.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

White Paper – Choosing the Right Spring Loaded Connector
In today’s cost-sensitive world, designers are often driven to specify the lowest cost solution for every aspect of their designs to ensure that their solution is competitively priced and their company remains profitable. However, specifying a low-cost, low-quality connector solution can result in premature failure, considerable re-work costs and damage to reputations. Download Now
eBook – Own the Lifecycle: Sustainable Business Transformation
Increasingly, product and services companies are seeking more information and control in the operational lifecycle of their products, including service and use. Better information about the operational lifecycle, and the ability to use that information, requires more than just unstructured data flowing back from products in the field. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close