Design Load on Overhead Clearance Bar
Design Load on Overhead Clearance Bar
(OP)
Hi all,
I have a project to design an overhead clearance bar / headache bar. It does not have a swing-away capability. I know ASCE 7 chapter 4 prescribes a 6,000 lb force for barrier systems applied at I believe 18" above grade, but certainly this isn't a barrier and doesn't need to function as one. So, the 6,000 lb seems a bit large to me. However, the force will be applied at the top of the bar, inducing quite a large moment at the base, so I need to select a manageable force, but also design appropriately.
Does anyone have any guidance on what magnitude of a point load might be appropriate here? I'd like it to withstand an occasional bump at height, or at least not completely get knocked over by one.
Thank you for your advice,
I have a project to design an overhead clearance bar / headache bar. It does not have a swing-away capability. I know ASCE 7 chapter 4 prescribes a 6,000 lb force for barrier systems applied at I believe 18" above grade, but certainly this isn't a barrier and doesn't need to function as one. So, the 6,000 lb seems a bit large to me. However, the force will be applied at the top of the bar, inducing quite a large moment at the base, so I need to select a manageable force, but also design appropriately.
Does anyone have any guidance on what magnitude of a point load might be appropriate here? I'd like it to withstand an occasional bump at height, or at least not completely get knocked over by one.
Thank you for your advice,






RE: Design Load on Overhead Clearance Bar
RE: Design Load on Overhead Clearance Bar
Their design is to have the vertical HSS welded to a base plate...I am also thinking of over designing the footing to try and ensure that whatever force I go with for the clearance bar, the plate will yield long before we have footing issues, thus making replacement easier.
I was thinking 1000 lb at the top for the steel components, and then doubling that for the foundation design...thoughts?
RE: Design Load on Overhead Clearance Bar
RE: Design Load on Overhead Clearance Bar
Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries
www.americanconcrete.com
RE: Design Load on Overhead Clearance Bar
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RE: Design Load on Overhead Clearance Bar
RE: Design Load on Overhead Clearance Bar
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RE: Design Load on Overhead Clearance Bar