Ridgerunner
Garden Master
- Joined
- Mar 20, 2009
- Messages
- 8,229
- Reaction score
- 10,064
- Points
- 397
- Location
- Southeast Louisiana Zone 9A
How much does that thing weigh? I know you got it home but are you going to have to get a crane to lift it? You make it sound awfully heavy. Not sure how pretty you want it to be either. I suspect you want it to look decent and not too redneck.
It's going on uneven ground, that argues for posts. I tend to agree with Bob, 4x4's are not strong enough for the 2 post build but would work fine for the 4 post version. I'd think a 4x6 would work but 6x6 would be stronger. If your ground is that soft you can put guy wires or even diagonal wooden braces to help hold it in place. With guy wires a 4x4 should work. That goes back to the A-frame design.
In soft ground, especially clay, you have two potential problems. Especially in clay that thing might just keep sinking. Clay is bad for that, especially when it is wet but sand works really well to stop it from sinking on down. A lot depends on your soils. You may need to put something under those posts in clay to keep them from sinking. A concrete pad would work. Another option would be to put some big nails or lag screws maybe in the bottom of the posts but sticking out enough for the concrete to grab them. That firmly attaches the bottom of the leg to the concrete and stops it form punching through if that makes sense. You are making a footing. That should take care of the axial force.
I don't know how high you want the tops of those posts, but sinking the posts three feet in the ground is probably a good idea. To stop it from wallering loose due to back and forth, you need good support on the sides at the bottom of that post but also at the top of the ground. Concrete at the bottom of that post and at ground level will do you more good than concrete just halfway up the post. To get technical you are creating a resisting moment and the further apart you can put the supports the stronger it will be. Maybe this will explain it better. If you hold a baseball bat at the top and bottom with your hands and someone tries to twist it you can resist pretty easily. But if you put both of your hands together on one end and they try to twist you can't stop them. So horizontal support at the soil level and the bottom as far apart as you can get them. Don't just bring the concrete partway up.
I don't know how far apart you plan to put your posts. Your connections at the top will be pretty close to the posts not out in the middle. I'd think one 2x6 with the flat side vertical would probably be enough, but two will be a lot stronger.
It's going on uneven ground, that argues for posts. I tend to agree with Bob, 4x4's are not strong enough for the 2 post build but would work fine for the 4 post version. I'd think a 4x6 would work but 6x6 would be stronger. If your ground is that soft you can put guy wires or even diagonal wooden braces to help hold it in place. With guy wires a 4x4 should work. That goes back to the A-frame design.
In soft ground, especially clay, you have two potential problems. Especially in clay that thing might just keep sinking. Clay is bad for that, especially when it is wet but sand works really well to stop it from sinking on down. A lot depends on your soils. You may need to put something under those posts in clay to keep them from sinking. A concrete pad would work. Another option would be to put some big nails or lag screws maybe in the bottom of the posts but sticking out enough for the concrete to grab them. That firmly attaches the bottom of the leg to the concrete and stops it form punching through if that makes sense. You are making a footing. That should take care of the axial force.
I don't know how high you want the tops of those posts, but sinking the posts three feet in the ground is probably a good idea. To stop it from wallering loose due to back and forth, you need good support on the sides at the bottom of that post but also at the top of the ground. Concrete at the bottom of that post and at ground level will do you more good than concrete just halfway up the post. To get technical you are creating a resisting moment and the further apart you can put the supports the stronger it will be. Maybe this will explain it better. If you hold a baseball bat at the top and bottom with your hands and someone tries to twist it you can resist pretty easily. But if you put both of your hands together on one end and they try to twist you can't stop them. So horizontal support at the soil level and the bottom as far apart as you can get them. Don't just bring the concrete partway up.
I don't know how far apart you plan to put your posts. Your connections at the top will be pretty close to the posts not out in the middle. I'd think one 2x6 with the flat side vertical would probably be enough, but two will be a lot stronger.
