1/2 inch anchors for hollow concrete block? Must resist pull out.

A costumer wants 7 foot ceder posts attached to the side of landing made of concrete blocks topped with brick. A hand rail will be attached to the posts and a flat ceder board attached to the top of the posts that will serve as a plant shelf.
I'm not sure if a concrete slab lies under the brick? The landing is about 30 inches high. What ever anchors I use must resist pull out forces from the railing and shelf.
Do appropriate anchors exist for what I want to do?
Thanks for any help!
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If they are concrete blocks (not that crappy dark grey stuff) toggle bolts would work.
Or look here:
http://www.simpsonanchors.com /
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Thank you! I found this:
http://www.simpsonanchors.com/catalog/mechanical/titen-hd/rod_hanger.html
But think the toggles you suggested will be more simple,
http://www.simpsonanchors.com/pdf/catalogs/C-SAS-2009/C-SAS-2009-p178.pdf
If I can't find ones long enough I can just substitute threaded rod. Great idea, thank you!
http://www.simpsonanchors.com/pdf/catalogs/C-SAS-2009/C-SAS-2009-p178.pdf
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The first thing I noticed was that you're going to have 7 foot posts attached to a cement block landing (wall) which is 30" high. Those posts then have to support both a handrail and also a shelf that will be loaded with plants. The plants in particular will presumably be high up and could be of substantial weight. That could put substantial leverage on the landing and fasteners.
My first concern would be how sturdy the block landing is to begin with. Often these things are thrown together with minimal cement and aren't intended to be structural supports for anything else.
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On 5/21/2011 12:46 AM, snipped-for-privacy@optonline.net wrote:

Excellent points. I'll also throw in that the plant shelf need a tall lip (with drain ports) to keep pots from landing on heads (especially shorter people like kids) if somebody slams into the railing, like when they stumble, or are horsing around.
Personally, I'd try to steer customer to hanging baskets, perhaps from a gibbet and pole, or even an arch, sunk into the ground. And if they need a handrail, wrought iron (real or faux) on anchors drilled/epoxied into the slab. Wood rail and brick porch would look funny to my eyes.
--
aem sends...

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Stick a Sonotube down in the ground at the edges and mount the posts on that. Too risky on just the blocks IMO.
Joe
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wrote:

Stick a Sonotube down in the ground at the edges and mount the posts on that. Too risky on just the blocks IMO.
Joe
ditto on that. Not enough to drill to. On some blocks, there is enough meat to use a 3/8" sleeve anchor successfully, but I would not trust a 1/2". Can you grout just that cell?
Steve
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As per the other posts, unless your certain of the design & constrctuion of the block portion of the landing, attaching a 7' post to blocks and expecting them to resist side loading could be a recipe for disaster.
The blocks and landing were probably designed & built with vertical (gravity) load only in mind. Ungrouted (hollow) cell block construction is is fine for gravity load but attaching posts / railing to them is expecting a lot.
You could drill into the side of the landing to probe for whether a slab exists. I would recommend embedding a threaded rod with a coupling nut into the slab & block using an epoxy product like SIKA AnchorFix #1.
Drill a 9/16" hole for the rod & counter bore a hole big enough & deep enough to accept the coupling nut. Embedding a rod & coupling nut will provide with a strong & flush attachment. You can then attach the post with hex bolts. Prior to attaching the post you could test the strength of the attachment with a bolt, steel plate & large diameter stub pipe.
Using this setup you can determine if the embed will hold under substantial force....if you can "jack" the embed out of the stab by tightening the bolt I would have doubts about using it for a railing.
The attachment at the lower end of the post might be more problematic.
If the post needs to be able to take ~150 lbs lateral load, the upper attach point needs to take ~500 lbs, the lower attach point a bit less (depending on the location of the upper attach point)
Long answer for a simple question.... how much can you depend on a hollow block structure?
cheers Bob
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wrote:

As per the other posts, unless your certain of the design & constrctuion of the block portion of the landing, attaching a 7' post to blocks and expecting them to resist side loading could be a recipe for disaster.
The blocks and landing were probably designed & built with vertical (gravity) load only in mind. Ungrouted (hollow) cell block construction is is fine for gravity load but attaching posts / railing to them is expecting a lot.
You could drill into the side of the landing to probe for whether a slab exists. I would recommend embedding a threaded rod with a coupling nut into the slab & block using an epoxy product like SIKA AnchorFix #1.
Drill a 9/16" hole for the rod & counter bore a hole big enough & deep enough to accept the coupling nut. Embedding a rod & coupling nut will provide with a strong & flush attachment. You can then attach the post with hex bolts. Prior to attaching the post you could test the strength of the attachment with a bolt, steel plate & large diameter stub pipe.
Using this setup you can determine if the embed will hold under substantial force....if you can "jack" the embed out of the stab by tightening the bolt I would have doubts about using it for a railing.
The attachment at the lower end of the post might be more problematic.
If the post needs to be able to take ~150 lbs lateral load, the upper attach point needs to take ~500 lbs, the lower attach point a bit less (depending on the location of the upper attach point)
Long answer for a simple question.... how much can you depend on a hollow block structure?
cheers Bob
Not much. If the codes required the cells to be grouted say every six feet, then the OP could fill the cells that were say three or four cells each side of the area in question. But what's to say how deep the rebar is, and if doing that would make it any stronger?
I used to be a steel erection contractor, and had a few scenarios like this. On one in particularly, we made a span overhead with a nice design to it out of ornamental metal, and put two posts on the sides, and attached it to the block with Tapcons where we could hit the thicker parts of the blocks. The rigidity of the added arch and side posts took most of the weight and banging of the gate that was in the center. But, not knowing the OP's particulars, digging the postholes may be the bugger, particularly if they are concrete. In that case, perhaps the use of steel baseplates RedHeaded into the concrete?
Gets into overkill and complicated construction, but you can only make so much ice cream out of so much horse manure, and sometimes you have to almost make a new structure because the old one is so flimsy it won't hold up what you want to hold up.
How about it, OP? Some baseplates RedHeaded into concrete, some posts welded on there, and a top spreader bar to strengthen and stabilize it? One of those four posted little arches over gates that people plant vines on? Just some rigid frame disguised as part of the deal?
Steve
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