bollard design
bollard design
(OP)
Need to design a couple of bollards to replace existing corroded away bollards that are at the roll-up doors of a police station. They are on an existing concrete slab. Is there anywhere that I can find a standard bollard design detail for this, or do I have to design it myself? There must be someone who has seen a well thought out typical detail.
I would think that would comprise a 42" high minimum (60" if visibility is a concern), minimum 6.5" O.D. minimum schedule 40 steel pipe, galvanized, filled with 35 MPa concrete, base plate of appropriate thickness welded with appropriate weld size, and 4 Hilti galvanized or s/s adhesive anchors of appropriate diameter. Painted yellow (after treating the galvanized surface appropriately so paint will adhere) for best visibility. Any detail that anyone can refer me too?
I would think that would comprise a 42" high minimum (60" if visibility is a concern), minimum 6.5" O.D. minimum schedule 40 steel pipe, galvanized, filled with 35 MPa concrete, base plate of appropriate thickness welded with appropriate weld size, and 4 Hilti galvanized or s/s adhesive anchors of appropriate diameter. Painted yellow (after treating the galvanized surface appropriately so paint will adhere) for best visibility. Any detail that anyone can refer me too?






RE: bollard design
If you must use a baseplate with post installed anchor bolts then that would be the area to design. I'd use something like a 20 kip impact or the force to cause yielding in the concrete filled pipe, whichever was lower, and size your anchor bolts to resist that moment and shear. I'd size the bolts so steel yielding controlled that way you can dissipate the impact forces using inelastic distortion. But, I'd only do this if for some reason digging into the ground wasn't permitted. I'd use a precast bollard before I'd try to anchor it using post installed anchor bolts.
Professional and Structural Engineer (ME, NH)
American Concrete Industries
www.americanconcrete.com
RE: bollard design
E.g. example of anti ram-raid bollards.
http://www.industrialsuppliesco.co.uk/details/Boll...
http://www.barriersdirect.co.uk/bollards-c1022/sec...
RE: bollard design
Just a guess, though. I personally try to specify off-the-shelf items whenever I can assuming it's not a huge cost difference.
Professional and Structural Engineer (ME, NH)
American Concrete Industries
www.americanconcrete.com
RE: bollard design
RE: bollard design
Found this bad boy kicking around the digital archives. Almost verbatim. I had nothing to do with this detail's creation.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: bollard design
There's often a similar structure on a boat, also called a bollard.
It usually has a crossbar, less often a rounded flange, to keep a hawser from slipping off the top.
On tugboats, they're made of really big steel tubing or pipe with really thick walls, and securely welded to the boat's structure from deck to keel.
My guys down at the marine exhaust shop designed and sold a really pretty one to a yacht captain, with a 3" dia barrel and a 1-1/2" dia cross bar, both made from our best stainless steel tube, #12 gage, beautifully welded to a nice square flange and mirror polished.
After it was shipped and installed, they asked me to give it a load rating.
I figured the tubing would fold at 3 kips or so,
and asked them not to sell any more bollards.
It should do well holding the dinghy painter...
</tangent>
Mike Halloran
Pembroke Pines, FL, USA
RE: bollard design