Subject: RE: Public Fence Sliding Gate Lateral Load
From: "Sprague, Harold O." <SpragueHO(--nospam--at)bv.com>
Date: Thu, 18 May 2000 10:46:09 -0500
Your right. This is an area that does not have much guidance.
If the gate is just for pedestrian traffic, I would look at the guard rail
LL ( 50 plf or 200 lb concentrated load) requirements as well as the wind
and seismic. If the gate area has potential for passenger vehicle impact, I
would look at the vehicle barrier loads (6000 lbs). If the gate area has
potential for truck vehicle impact, I would look at the AASHTO vehicle
barrier loads (10 kips). Obviously there is a lot more definition to these
loads in the various UBC or AASHTO codes.
For the wind loads:
If the wire mesh is cylindrical, you should consider the Open Signs &
Lattice Frameworks Cf values on p 67 of the ASCE 7-98. It is the best thing
written to date that covers your application. It has a provision for
rounded members and for the ratio of solid to gross area.
The ASCE 7-98 is the best yet for wind loads.
> -----Original Message-----
> From: Canitz, Charles F NAB02 [SMTP:Charles.F.Canitz(--nospam--at)nab02.usace.army.mil]
> Sent: Thursday, May 18, 2000 7:54 AM
> To: 'seaint(--nospam--at)seaint.org'
> Subject: Public Fence Sliding Gate Lateral Load
> Regarding the design of fence sliding gates used in areas accessed by the
> public, are prescribed lateral design loads available(similar to that used
> for stairs and ramp guardrails) which account for spectator use? This is
> issue with a particular project which I'm involved since the gate
> columns are structure supported(i.e., precast concrete double tees with
> concrete topping) in lieu of ground supported. The gate is 10 feet high
> the framing consisting of HSS's as the horizontal top and bottom and
> intermediate vertical framing with 2" square wire mesh as the fabric
> I'm presently using wind load(assuming a sign with openings/open lattice
> framework condition) as the lateral load but am now wondering if I'm being
> too conservative. Naturally, the project specs do not provide any gate
> prescribed lateral design loads.
> Charlie Canitz, PE