Bolting down a fence-post support to a concrete base?

[Lobster]

I need to erect a short paneled fence across an area of concrete, and am going to support a post using one a bolt-down support like this:

What's the best method of bolting this down? I don't quite know how good condition the concree wil be in (and notably, how deep) till i start attacking it (and it's not at my home, so preferably I need to be able to just pitch up with the right kit and do the job there and then).

If I use anchor bolts of some sort, if they end up in a vertical, blind-ended hole aren't the components susceptible to rainwater corrosion? Are some sort of resin-based fixings better (don't know much about them?)

Thanks

[Bob H]

To ascertain the thickness of the concrete, you could do this in 2 ways.

1, find an edge of the said concrete, if it is close to where you would be placing the post, and measure it.

2, drill a small pilot hole where the post bracket will sit, and then you can get a feel of how hard the material is. If it feels soft, then that is soil.

I am fairly sure that there are anchor bolts of different lengths, and as the weight is downward, it won't really matter if the said bolts are fairly short. You only want enough of the bolt in the concrete to stop sideways movement, and easy pull out/up.

[larkim]

I think I used these Fischer FBS concrete screws when bolting down similar posts into paving slabs.

Worked surprisingly well for me (were a recommendation from TMH I think).

Matt

[Martin Bonner]

Err? The biggest load is going to be when someone pushes the fence. One side of the support will be pressed into the concrete (and won't move); the other side will be lifted up, and will be relying on the pull-out resistance of the bolts to hold it down. Given the posts are going to act as a lever, that's going to be a pretty large pull-out force.

[Alan Braggins]

Or the wind does....

[The Medway Handyman]

posts into paving slabs.

Thats what I was going to suggest, but these are the same but cheaper;

[GMM]

When I moved into my house, it had a disabled hand rail fitted by the front door, basically some scaffold pole with brackets. That was screwed into the concrete step using something that was a bit flexible like hard rubber, but may well have been a variant of resin. Whatever it was, it was 'king hard work getting the three 2-inch screws out. I had to cut one of them off flush in the end (well at least that brought an angle grinder into the thread....)

[Lobster]

I've never seen these before; are they genuinely any good? Seems hard to believe that they are my best option?.... it's not by any means fresh concrete that they are going into; furthermore these really need to be strong, as there is a 6-foot drop on the other side of the fence, and this needs not to fall down there...

[Lobster]

Well, for better or worse I went with resin fixings. Seems OK, but a lot of faff compared with the concrete screws - I'll definitely try those some other time, when it's less mission-critical.

Follow-up q...

I've now got all these exposed non-stainless steel studs, bolts, nuts and washers on the steel fence post bolt-downs. How do people generally inhibit these from corroding? Cover them with paint? Or a generous coating of grease and hope for the best?

I'd like to think these will outlast the fence and still be around to re-use with new panels in X years time!

[F Murtz]

You can get stainless dynabolts.