Pedestrian railing on a retaining wall

[Hemifun]

I am designing improvements to an existing retaining wall that is located along a City street and acts as a shoreline wall with a beach on the front and the street behind it. The wall is from 3 to 10 feet high. There is a 6 foot wide sidewalk immediately behind the wall. There is an existing pipe railing mounted on top of the wall that the City would like replaced. My question is, what code would govern the design of the new pedestrian railing? I know the IBC has standards but this isn't a building or a path of egress. I'm not sure OSHA would apply since this isn't a work site. AASHTO has pedestrian railing stds. for bridges but this isn't a bridge. This is simply a half mile long sidewalk along the lakefront which also happens to be along the top of a retaining wall. Any suggestions??

 

[ACtrafficengr]

Check to see if your state DOT has a pedestrian handrail specification you can use off the shelf.

Is the top of the retaining wall in the clear zone of the adjacent street? Should a vehicle guide rail be used?

"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

 

[Ron]

In the absence of a DOT requirement, I would use the IBC criteria.

 

[MiketheEngineer]

You might also have to consider ADA?? and while IBC might not be the way to go - it does say that railings like in a loft area must restrain a 4'' "ball" from going through.

Not really a bad idea when it comes to kids being around areas like this?? 10' is a long way to fall for anybody - esp a 2 year old adventurer....

 

[OHIOMatt]

I agree with Mike. The IBC refers to these as guard rails. They have specific load criteria and dimensional criteria. I just finished a retaining wall project and we used a decorative fence that met the load and height criteria. If memory serves, it is 50 plf at the top of the rail (42" above grade) or a concentrated load of 200 lbs any were.

 

[Hemifun]

Thanks for the comments. ACt, I did check the clear zone and we are ok as far as that goes. The State DOT has a section in their design manual that talks about "protective rails" which has the max. 4" opening requirement but their own railing detail for bridge pedestrian railing shows a 6" opening which I find a little confusing. Another consideration is the fact that this wall and railing is subject to significant poundings by waves and ice during winter storms. I have seen photos of ice dunes completely over the railing and into the street as a result of a storm, forcing the City to close the road. While it looks like most are recommending the max.4" opening railing, I'm sure the City will balk at that due to the additional surface area which will catch the wind, waves and ice forces. Decisions, decisions.

 

[bridgebuster]

Generally, 4" is recommended to prevent a small child from climbing through the picket fence. If you want to use the 4" spacing go on record with the city that it's in their best interest for safety & liability reasons. Let them tell you no.

 

[cvg]

typical railings for city streets located on walls (such as headwalls, wingwalls and retaining walls) are pipe railings. 8 foot spacing on vertical posts and 3 horizontal rails. Typically 42 inches tall. If you are worried about children then install a chain link fence. If you are worried about climbing and jumping over, put barb wire on top.

 

[MiketheEngineer]

And I usually spec vertical rails at 4'' oc. Horizontal rails will meet code - but also make good ladders for little ones. As noted - chain link and barbed wire will work well - esp if you like the institutional (prison)look.

Vertical rails may capture less water and ice?? Actually those loads may really govern the design!!

 

[Hemifun]

These are all excellant points, thank you. Cvg, you mention the typical pipe railings along city streets. This is essentially what is there now. Do you have any codes, standards or references to support this?

 

[dik]

If public has access, go with the 4" picket spacing...

Dik

 

[cvg]

building codes typically do not apply to streets and highways. Standards are typically local ones required by the City, County or State Highway Department. You should be getting this from the street department in the county or city you are working in. Attached is an example of a local (county) standard for railing used on walls similar to your project.

 

[a2mfk]

cvg's detail is the standard Florida DOT handrail you see everywhere on the side of retaining walls and sidewalks with drop offs. Actually, to the point of why the hell did they waste their money on that handrail next to a one foot drop off (seriously, they are everywhere and its a total waste half the time- lawyers I assume are to blame).

Anyway, if you want another go by I am sure you can find the same FDOT details online.

But the guys all make great points about the 4" spacing, this wall you describe sounds like a safety issue with children but as you stated it also may act as an ice dam. You may be dammed if you do or dammed if you don't, oh yeah, intentional pun.

I would want your client to answer this in writing to CYA. Another question for the city's attorneys instead of common sense engineering and good parenting

 

[BAretired]

You can do anything you like, unless of course you are operating in the State of Pennsylvania in which case you must abide by the Pennsylvanian handrail, tire and girdle legislation enacted in 1832.

BA

 

[bridgebuster]

BA - could you elaborate? As a non-native Pennsylvanian it took some time adjusting to the culture shock, but I couldn't find anything about the handrail etc act of 1832.

 

[Hemifun]

BA, I do live and work in PA and said act would apply. However, this particular project is in NY. Hmmmm, I wonder if NY has a similar law?

 

[bridgebuster]

hemifun - if you're project is for NYC (I wonder if we're working for the same client), City DOT has a standard sheet for picket fence railing, which calls for 3 1/2" bar spacing.

 

[Hemifun]

No-- I'm at the opposite end of the State along Lake Erie.

 

[bridgebuster]

You're lucky; mine's the client from someplace worse than hell.

 

[Hemifun]

LOL I thought that too but didn't say anything.