I don't mind admitting: I've never "gotten" banding. 2

[3doorsdwn]

It may be a bit embarrassing for a engineer to admit it at this point in his career......but I was looking at a grating shop drawing today and thinking to myself: "what does the banding/toe plate really do as far as load transfer goes? Does it run load from the weak axis of the grating to the strong axis? How do you check it? With the banding as a beam or more as shear transfer element? Are there good rules of thumb for opening sizes [with respect to this]?"

Any insight is welcome.

 

[JStephen]

It hadn't occurred to me that it had a structural purpose. Don't the same load tables apply either way?

 

[hokie66]

Banding bars are just to finish the ends, like a fascia. Kick plates are the same, but also serve a safety purpose, in supposedly stopping things from being dropped off grating floors.

 

[3doorsdwn]

Structurally it must serve some purpose because you never see someone call a portion of grating a cantilever just because someone puts a 10" hole in the grating at the mid-point between support points for the grating. I've just never gotten how to evaluate that structurally. It would seem that if you are disrupting that many bars and only replacing it with one......you'd think something would have to be quantified .....but I've never seen it done.

 

[racookpe1978]

Much of it is appearance - but having hundreds of "naked" points sticking out of the ends of every grating in every platform are dangerous "pokers". Also, running lines, temporary cords, chainfalls, hoses, power cords, buckets, and everything else past the jagged "points" of an unbanded grating will screw up construction and maintenance significantly.

But construction and maintenance savings can't be the real reason for banding - after all, construction and maintenance are not high concerns any other time of the design and purchasing process. 8<)

 

[MikeHalloran]

In the US, the banding _must_ be there to satisfy OSHA requirements for a toe plate, which is intended to keep people (not wrenches) from sliding off the grating under the handrails when things get slippery, e.g., when the peanut butter hits the fan.



Mike Halloran
Pembroke Pines, FL, USA

 

[JStephen]

Mike, do you have OSHA references for either the banding requirement or the requirement for a toeboard to keep people from sliding under a handrail?

 

[Duwe6]

Banding is recommended [good indeustry practice], but toeplates that extend 4-inches or more above the grating is mandatory.

This makes the toeplate at least 5-inches tall 'deep', and it can carry significant loads. I have every other grating bar welded to the toeplate at grating penetrations. This will carry the deck load around penetrations up to about 2-ft in diameter.

 

[MiketheEngineer]

Look in OSHA 1926 part 450 - Scaffolding for toe board requirements. It is typically a nominal 2x4 - 3.5'' actual. CAL-OSHA is different - 2x6

 

[JStephen]

I'm familiar with the requirements for having toeboards. But I don't recall ever seeing any statement that implied they were to prevent people from sliding through, nor any requirement for grating to be banded, and those were the points where I wondered about.

 

[hokie66]

Where I am, the kickboards are connected to the balustrade posts, not the grating.

 

[MiketheEngineer]

#1 They tend to prevent tools/material from getting kicked off the decks.

#2 They do tend to keep people from rolling under the mid rail - though not always.

Had a tragic accident a few weeks ago near the St. Louis area. Welder was welding guard rail post on a tank. Temp was over 100F.

He apparently passed out and rolled under the mid rail 50' to his death. He may have had a heart attack.

No toe board had been installed yet.

 

[ToadJones]

hokie-
Im in the states and typically weld toe plate to handrail posts.

 

[hokie66]

Yeah, that's the way we did it when I was there. Providing it as part of the grating must be a new thing.

 

[Duwe6]

Perimeter toeplate welds to the handrail sections, typically as part of the shop fabrication. Using toeplate to reinforce grating penetrations, like when the pipefitters cut a hole to let a pipe go down thru the grating, is a different matter. That hole has to be reinforced, and OSHA and good safety practices requires that that pennetration have a toeplate. Easiest to let the toeplate provide the reinforcement.

Banding around the edges of a section of grating keeps the raw, cut ends of the grating bars from being a snag hazard. It also makes sections of grating easier to remove and reinstall.

 

[TXStructural]

29 CFR 1910 is the OSHA general industry code 29 CFR 1926 is the construction industry code. Fixed locations with "normal" employment are general industry. Construction industry rules apply to construction and certain, special maintenance conditions in completed facilities, but not routine maintenance activities by regularly-employed maintenance staff.

Toeboards are to prevent tools and materials from falling on to people or equipment below, or into hazardous operations. They are not part of a standard railing as required for all elevated walking and working surfaces. I think it is a terrible oversight to allow upwards of 20" between the floor and mid rail on a 42" high standard railing.

Below is excerpted from osha.gov:

1910.23(c)
"Protection of open-sided floors, platforms, and runways."...
1910.23(c)(2)
Every runway shall be guarded by a standard railing (or the equivalent as specified in paragraph (e)(3) of this section) on all open sides 4 feet or more above floor or ground level. Wherever tools, machine parts, or materials are likely to be used on the runway, a toeboard shall also be provided on each exposed side.

and

1910.23(c)(3)
Regardless of height, open-sided floors, walkways, platforms, or runways above or adjacent to dangerous equipment, pickling or galvanizing tanks, degreasing units, and similar hazards shall be guarded with a standard railing and toe board.

and

1910.23(e)(4)

A standard toeboard shall be 4 inches nominal in vertical height from its top edge to the level of the floor, platform, runway, or ramp. It shall be securely fastened in place and with not more than 1/4-inch clearance above floor level. It may be made of any substantial material either solid or with openings not over 1 inch in greatest dimension.

Where material is piled to such height that a standard toeboard does not provide protection, paneling from floor to intermediate rail, or to top rail shall be provided.

 

[csd72]

Not 100% sure what banding is but by the sounds of things it is there to provide lateral restraint at the ends of the span.

Intermediate banding also provides lateral restrain and spreading of foot loads across several 'beams'.