Heavy-duty joist hanger for vertical cut blocks

[mmx]

Hello,
I need to secure the dock on the east coast and am considering attaching joist hangers (for 45x195 or 90xx195) to a vertical rock face.
Are there any heavier-duty hot-dipped galvanized or stainless steel joist hangers? The ones I find have such small holes (11mm) for the bolts into the rock... or will 10-11mm suffice?
Or do you have any other tips on the best way to attach the beams to the rock? A horizontal ledger board might not work so well, the rock is quite round.

 

[Peter2400]

Hello,
I need to secure the dock on the east coast and am considering installing joist hangers (for 45x195 or 90x195) on a vertical rock face.
Are there any heavier-duty hot-dip galvanized or stainless steel joist hangers? The ones I find have such small holes (11mm) for the bolts into the rock... or will 10-11mm suffice?
Or do you have any other tips on how best to secure the beams to the rock? A horizontal bearer might not work so well, as the rock is quite round.

There are rock brackets, you should be able to come up with something using those.
I wouldn't trust a regular joist hanger.

 

[mmx]

Well, I've found them, they look good, but about 2000:- each and only extend 150 cm. Can't find any specifications either.
And if you look at the attachment, it's just two angle irons, should be possible to achieve the same strength with sturdy joist hangers?