I know this thread is old and dead, but it was a return when i was looking for a IRC reference. I design a lot of guardrails... 12kips at 36 inches sounds outlandish. Where is that from?
AASHTO '89 is 10k at about 22" (they have details), with 5k in non-primary barirer directions (longitudinal/inward/etc). IBC goes directly to ASCE7 which is 6k at 18" minimum, but acting in any horizontal direction, and specifically precludes busses and "trucks" (meaning actual trucks like SU-30, not that humvee). Those values are for traffic collision, and are mainly to guide traffic back onto a road. The 6k is in line with testing of guardrail systems, which shows around 5.9k for a light duty vehicle at ±20° at a low speed threshhold collision.
I would presume an "approved barrier" per the IRC would be something like a traffic railing rather than an intended impact mechanism, like a loading dock. In that case, i would anticipate an official would accept my design per IBC, which is ASCE7. Conversly, something like a vehicle barrier on a loading dock is designed for a 100k impact force as semi-trailers intentionally ram it downhill. The semi could go through the bollards and right on through the rest of the house. I design industrial barriers for anything between 6k and 10k, at the client's request. I design push walls for front loaders for anything between 30k and 130k. A front loader could also go right through a house. None of those higher loads would make sense to me from a design perspective for the IRCs intent. I'd say use 6k @ 18" or a little higher if you want.
AASHTO '89 is 10k at about 22" (they have details), with 5k in non-primary barirer directions (longitudinal/inward/etc). IBC goes directly to ASCE7 which is 6k at 18" minimum, but acting in any horizontal direction, and specifically precludes busses and "trucks" (meaning actual trucks like SU-30, not that humvee). Those values are for traffic collision, and are mainly to guide traffic back onto a road. The 6k is in line with testing of guardrail systems, which shows around 5.9k for a light duty vehicle at ±20° at a low speed threshhold collision.
I would presume an "approved barrier" per the IRC would be something like a traffic railing rather than an intended impact mechanism, like a loading dock. In that case, i would anticipate an official would accept my design per IBC, which is ASCE7. Conversly, something like a vehicle barrier on a loading dock is designed for a 100k impact force as semi-trailers intentionally ram it downhill. The semi could go through the bollards and right on through the rest of the house. I design industrial barriers for anything between 6k and 10k, at the client's request. I design push walls for front loaders for anything between 30k and 130k. A front loader could also go right through a house. None of those higher loads would make sense to me from a design perspective for the IRCs intent. I'd say use 6k @ 18" or a little higher if you want.
