[SML] Loading Bridge design...

Wed Jun 4 16:09:34 UTC 2025

Code from the way back is vague...
https://ia904608.us.archive.org/28/items/standardbuilding00unse/standardbuilding00unse.pdf
Section 4-14 (pdf page 14) covers places of assembly.

Any idea who built the system? If the company is still around they may have an archive that would have the stamped engineering drawings. That would be the definitive way to know if the bridge was designed adequately in the first place (but you know its at least close, since it is still there after all these years).

Beyond that, 20psf  sounds like a typo, but the cure will probably be bringing in an engineer (and the first thing they will ask for are the stamped drawings).

I can respect that you don't want to share your clients name and location, but if you can send pics of the arbors, locks, and blocks the 'elder experts' can probably tell you who made it.

Tyler Smith

(he/him)

Performing and Fine Arts TD/PM

________________________________
From: Stagecraft <stagecraft-bounces at theatrical.net> on behalf of stagecraft-request at theatrical.net <stagecraft-request at theatrical.net>
Sent: Wednesday, June 4, 2025 5:00 AM
To: stagecraft at theatrical.net <stagecraft at theatrical.net>
Subject: Stagecraft Digest, Vol 130, Issue 3

*** EXTERNAL EMAIL: Do not click links or open attachments unless you recognize the sender and know the content is safe. Forward suspicious messages to abuse at up.edu. ***

Send Stagecraft mailing list submissions to
        stagecraft at theatrical.net

To subscribe or unsubscribe via the World Wide Web, visit
        https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Ftheatrical.net%2Fmailman%2Flistinfo%2Fstagecraft_theatrical.net&data=05%7C02%7Csmitht%40up.edu%7C7ed9d1c44bc144d13ba708dda369c12a%7Cea8f3949231c40b6a33f56873af96f87%7C0%7C0%7C638846397082302156%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C80000%7C%7C%7C&sdata=gsPgPWmCRd0F%2FAYBFn4172Nh0DM9HDUWVRE%2BdeXUZfM%3D&reserved=0<http://theatrical.net/mailman/listinfo/stagecraft_theatrical.net>
or, via email, send a message with subject or body 'help' to
        stagecraft-request at theatrical.net

You can reach the person managing the list at
        stagecraft-owner at theatrical.net

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Stagecraft digest..."

For list information see <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fstagecraft.theprices.net%2F&data=05%7C02%7Csmitht%40up.edu%7C7ed9d1c44bc144d13ba708dda369c12a%7Cea8f3949231c40b6a33f56873af96f87%7C0%7C0%7C638846397082329127%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C80000%7C%7C%7C&sdata=vl4H1RnO%2Bs35W8p%2FZ1wdDCWRYM0BIwnW%2BC%2FB7NDG3y0%3D&reserved=0<http://stagecraft.theprices.net/>>

Today's Topics:

   1. Re:  Loading Bridge design... (Matthew Breton)

----------------------------------------------------------------------

Message: 1
Date: Tue, 3 Jun 2025 15:21:43 +0000
From: Matthew Breton <theatricalmatt at hotmail.com>
To: "stagecraft at theatrical.net" <stagecraft at theatrical.net>
Cc: Will Leonard <will at istudioprojects.com>
Subject: Re: [SML] Loading Bridge design...
Message-ID:
        <DM4PR20MB57513F92AF08682EA3783825DA6DA at DM4PR20MB5751.namprd20.prod.outlook.com>

Content-Type: text/plain; charset="windows-1252"

Maybe the difference is between what they feel is required by code (ie, the minimum permissible) versus the actual load it needs to support?  20psf seems ridiculously low, especially when a loading gallery for a theater is likely to be holding around 10 tons of counterweight.

Given the dimensions of a steel counterweight (6" x 13" x 2") ? two across and two high would be somewhere around 200 lbs/s.f., no?  (Plus two burly stagehands....)

Matthew Breton  |   he, him, his
Design for Theater and Dance
________________________________
From: Stagecraft <stagecraft-bounces at theatrical.net> on behalf of Will Leonard via Stagecraft <stagecraft at theatrical.net>
Sent: Monday, June 2, 2025 11:10 AM
To: stagecraft at theatrical.net <stagecraft at theatrical.net>
Cc: Will Leonard <will at istudioprojects.com>
Subject: [SML] Loading Bridge design...

Howdy,

We are doing an install on a building that was built in 1976 & I need some information from the experts on the List:

 With this project, we are having to work with an Architectural Firm who has no theater experience. We are having to explain to them how things are actually work/are used, which is not a problem because this is very common as we deal with remodels, etc.

However, they are trying to tell us that the loading bridge is only designed for a Live Load of 20psf. This means that 1- we cannot build a scaffolding to reinforce the head steel (as they are requiring) but also that 2- the bridge cannot have the stage weights stacked on it as it was (& has been since the building first opened).

What I am looking for is if someone can quote (or direct me to where I can find) documentation that the building codes of the 1970s required Live Load ratings (150 psf? like the stage floor). I don't want the client to not be able to use their newly installed counterweight system because of incorrect information, so I reach out to the group to see if I am crazy.

Let me know what you think (dangerous request I know) ;)
- Will Leonard
Design Manager
C: 281-752-1060

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Ftheatrical.net%2Fpipermail%2Fstagecraft_theatrical.net%2Fattachments%2F20250603%2Fd023317e%2Fattachment-0001.html&data=05%7C02%7Csmitht%40up.edu%7C7ed9d1c44bc144d13ba708dda369c12a%7Cea8f3949231c40b6a33f56873af96f87%7C0%7C0%7C638846397082347325%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C80000%7C%7C%7C&sdata=%2BJkJ3yGPbkP4mThhapEgX8HYHoIo3P9PiqeBCWY0HVU%3D&reserved=0<http://theatrical.net/pipermail/stagecraft_theatrical.net/attachments/20250603/d023317e/attachment-0001.html>>

------------------------------

Subject: Digest Footer

_______________________________________________
Stagecraft mailing list
Stagecraft at theatrical.net
https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Ftheatrical.net%2Fmailman%2Flistinfo%2Fstagecraft_theatrical.net&data=05%7C02%7Csmitht%40up.edu%7C7ed9d1c44bc144d13ba708dda369c12a%7Cea8f3949231c40b6a33f56873af96f87%7C0%7C0%7C638846397082364339%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C80000%7C%7C%7C&sdata=TMuGFFkJhJCcj%2BJ%2BuTVchR9CzM6rhzGAwjLfuEHzbhk%3D&reserved=0<http://theatrical.net/mailman/listinfo/stagecraft_theatrical.net>

------------------------------

End of Stagecraft Digest, Vol 130, Issue 3
******************************************

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://theatrical.net/pipermail/stagecraft_theatrical.net/attachments/20250604/306cc992/attachment.html>