Retrofit Bracing To Threaded Rod Hanger Sytem

[BigErectBeam]

Hello, new to the forums here. On a manufacturing project one of the contractors decided to go a different route than was specified for installing some conveyor support hangers (I'm only an EIT and didnt want to open a can of worms by asking who approved the change). They went from a design that consisted of angles welded to gussets that threaded rods drop down from. These threaded rods then attach to proprietary conveyor support frames. Due to the layout of the roof and the complexity of the conveyor system, they prefered to use beam clamps instead of angles welded to gussets. The final system consisted of beam clamps to 3/4" rods, which run down to back to back C4 channels (with spacer bars b/w the channels). A second set of 5/8" threaded rods drop down from the channels and then attach to the proprietary supports. Ultimately they removed basically any stability from the system so significantly more bracing will be required. The problem we're having is how to actually add the bracing since the whole system (including the conveyors) has already been installed.

We want to use unistruts for the braces (there isn't much lateral loading this is really just meant to prevent rotations at the beam clamps, we will provide bracing at the level of the conveyor for the lower rods)but am at a loss as to how to attach the unistruts to the rods. As seen in the screenshot I've provided, we wanted to use angles but I don't see how these could be installed without shoring the conveyors and taking the system apart at the top by the beam clamps.

So my question is, has anyone dealt with anything like this before? Do they make any sort of clamp that can be used to attach the struts without disassembling the system to some degree?

 

[human909]

I've dealt with similar things.

Can you site weld? What is wrong with just site welding rod or Unistrut to the existing rods? Also have you asked the contractor to come up with a proposed solution? It was their screw up, let them do the hard yards in finding a solution.

Unistrut can be great on site but often it is a headache working out how to effectively use it from the desk. Good contractors can be innovative and effective if you let them do the thinking.

(Obviously 'letting' the contractors do the thinking is what got you into this mess. However for 'light' loads, light lateral restraints, industrial settings, I find that site solution are sometimes the easiest.)

 

[bones206]

This will be a good first resource to check:

https://www.unistrutohio.com/Content/Images/uploaded/cat-seismic-bracing-systems.pdf

Do they make any sort of clamp that can be used to attach the struts without disassembling the system to some degree?

See page 29.