×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Maximum Post Spacing for Decorative Railing

Maximum Post Spacing for Decorative Railing

Maximum Post Spacing for Decorative Railing

(OP)
I have a decorative rail along a stair case bolted to concrete posts at the top and bottom. The length along the rail between posts is up to 14.7 feet. I am using a 1.25" x 2.5" kick bar to meet AASHTO loading requirements for pedestrian rails. This seems like a heavy bar to use, but the top member is a 6" pipe. Is a 14.7 ft post spacing excessive? Should I place an additional post at mid height along the stairs?

RE: Maximum Post Spacing for Decorative Railing

Mu = 50 plf *14.7^2 * 12 / 8 = 16.21 k-in

Zx = 1.25 * 2.5^2 /4 = 1.95 in^3
M_allow = 36/1.67 * 1.95 = 42 k-in > 16.21 k - in

Looks like you are okay!!!!

But I am confused, is the 6" pipe your handrail or your guardrail? It is too big to be a handrail. I have never used the term "Kick bar" before, but I am assuming that is similar to a toe board?

RE: Maximum Post Spacing for Decorative Railing

I'd also be contemplating that the base of the posts must also resist the moment created by a fat mema stumbling and hitting that rugged handrail for a well alanced design.

http://cdn.lolbrary.com/2013/12/6/lolbrary.com_413...

RE: Maximum Post Spacing for Decorative Railing

(OP)
The 6" pipe is just decorative. I believe the architect called the bottom bar a kick bar. I looked at the loading on the bar in the other direction such that Zx = 2.5*1.25^2/4=0.98 and it still works. I guess I was looking or more of a rule of thumb for maximum post spacings. I can up size the bar to make it work, but then the rail will just look really heavy, and may not be economical.

RE: Maximum Post Spacing for Decorative Railing

I know what I think when I or someone else bump a railing etc and it begins to shake very visibly at some bending mode.

RE: Maximum Post Spacing for Decorative Railing

1. You have a single load limit (200 lbs sideways at the top of the rail.) AND a second, 50 lbs per foot limit for the rail overall. (Usually, posts are 4 ft apart, so the two are "about" equal.)

So, the 200 lbs requirement looks OK, but 15 ft x 50 lbs/ft = 750 sideways at the top (42 inch high for a guardrail, right?) on the post.

2. Don't confuse a "handrail" grip requirement at +36 (+/-2 inch) measured from the toe of each step on a stair, with the guard rail requirement for height. If the guard rail (only on commercial applications!) is horizontal, I do not see a "grip" requirement coming up for rail diameters.

RE: Maximum Post Spacing for Decorative Railing

concur on 'grip' not being part of a handrail requirement.

Toeplate = toeboard = kick plate when it comes to handrails.

One further note; [morons] at OSHA have specified 42" - period. What they did is to codify the old 3½-ft nominal rail height. Americans are now significantly taller than they were in 1901, and 42" is a little too low to be safe for anyone over about 5'-10" tall; their center of gravity is above the top of the OSHA-mandated rail. Most mezz handrails [all?] in malls have their handrails at about 44" to 48" tall. Much safer structure for the slightly above-average person.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources