Eternal Mystery of the Universe #1 - 1-1/4" Guardrail 1

[Guastavino]

This issue comes up all the time for me and how it came about is one of the eternal mysteries of the universe in my mind. I always tell folks they can't use 1-1/4" STD pipe guardrail because of the 200# concentrated force at 42" makes it such that it just doesn't work in bending. Then, I get the "well it's the way we've always done it". Code officials never seem to catch it, but it doesn't work unless you start to count on a FE model that spreads the load between posts, etc. And then it's still questionable at best IMO.

Then, I see arch's spec 1.50" O.D. handrail/guardrail, which of course doesn't exist in the Pipe shape realm. So I'm curious, A) how people justify using 1-1/4" (1.66 O.D.) std pipe guardrail, and B) what do you all tell clients if you're on the same side as me, that it has to be 1-1/2" STD Pipe (1.90" o.d.)

Thanks!

 

[thaidavid40]

If you're looking for a prescriptive design standard, then try the PIP STF05520 - "Details for Pipe Railing for Walking and Working Surfaces". The Process Industries Practice folks have a wealth of pre-configured, prescriptive, structural and civil design standards, which are used across many industries.
Dave

Thaidavid

 

[SAIL3]

since the H/R post most often is the weak link, I have used 2x2" tube for the posts, 1 1/2" std pipe for top rail and 1 1/4" std pipe for mid-rail...it also simplifies the fit-up/coping @ the mid-rail to post connection and results in more fleixibility in spacing the posts....