Need to fix a retaining wall

[Wakey]

I've got a ton of projects to do on the farm so I thought it might be fun to ask opinions before I start. I'll be happy to post pics as we go, along with the finished product.

Obviously the barn needs some TLC but with all the rain we have been getting, I don't want this crashing into the wall creating a bigger mess.

Remove some dirt with a backhoe, right?

I figured I'd rent one and dig up some stumps while I had it.

The wall is almost 5' tall if you stand next to the barn. It has 4x4 posts and 2x6 boards. I know, someone else's masterpiece here. Whats worse is that the boards are nailed to the back side of the posts.. I can't believe most haven't sprung loose. The pics don't really show it but it appears one or more of the posts came loose or it broke, and the dirt continues to settle.

I was going to dig a bit further than the failure to inspect the next 4x4 post, in each direction.

I was wondering what I might need to do to make sure this does not happen again. I've seen stronger walls, made with railroad ties and the like.

I've heard of using "dead men" to strengthen the wall.

I was thinking after the dirt is gone to concrete in about 4 new posts.

What do yall think?

 

[vtsnowedin]

First off, do you need the area above and behind the wall to be at that level? Could you just move the picnic table back and slope the ground down to a stable slope say three horizontal to one vertical?

 

[hosspuller]

Do the job right ... Wood rots. RR ties are rejected by the RR because they're rotten. Don't take on someone's rejects. Unless you intend to sell the place in a few years. I wouldn't buy it until the price reflected the issues.

 

[dragoneggs]

You could go concrete blocks. At 4 ft height, no engineering required but figure $10 per square foot of face DIY. Price based on Allen Block (8in by 18in by 12in and 75lb each) . Not sure what block sellers and pricing you have in your area. I am starting to build several walls for my sloped yard.

 

[Wakey]

We are long haul-ish mindset with everything we are doing here.

As for sloping it we really can't because opposite the barn is where we park tractors, implements and small trailers. Plus we walk a couple horses right around the barn to a paddock.

As for concrete.. How about cinder blocks with concrete poured inside? I have a nice pile of blocks I'd like to make disappear.

 

[the old grind]

No offense, but a mowing pattern obvious in the 1st pic says to me that the rain pro'ly had some help 'settling' what's behind the 'wall'. Moving the table nearer to the post later on might get you more years out of a rework if you're using one of the tractors to mow that close there. (Looks like no picnic to mow around the table either way.) That little slope towards the boards' top is scary too, if it allows runoff to collect along it. Looks like that has been 'snowballing' on you for a little while.

If digging is easily do-able, I'd start over and make sure the grade sloped away from the wall when finishing, touching up as it settled again to stay ahead of things. Looks like only the one post would need a dead-man, and that would seem to be a necessity. Any reason not to make that two posts & shorter boards if you replace them? Adding a drain tile behind the wall might be a bit much, but wouldn't have to be full depth (5') & need not be too close to it. (2'-3' & it's not a problem wet spot.)

btw: IMO, a dead-man doesn't need to be a 4x6 or heavy timber but the anchor(s) might want to be that or more, and you might want them both notched to not pull apart. An iron beam to connect anchor to post might rust to nothing someday, but might last a few decades before you dig/redo again later. Either mat'l, under a tension load might handle more force than what fastens the pieces together.

I guess I'm saying that PT wood is as good as masonry if done right. I'm sure it would run less $$, even with all new materials, but I'm way cautious and thinking of the fuss a redo in 20 yrs might be if it's needed again. Concrete & blocks stay hard, but they don't always stay exactly where you put them. How long has the old wall been there & held up as well as it has??

 

[jonnyc1999]

If you plan on staying there for awhile, I'd do like others suggest and replace the wall with stone. I only have experience with freestanding retaining wall systems but if you already have lots of cinder blocks on hand, I'd use them. Im not sure what sort of reinforcement you would need to do with a cinder block wall.


I have 2 retaining walls on my property, one being 150' long and 7' high. The system used was Anchor diamond pro blocks, with compacted stone dust for 7 ft back, with reinforcement mesh every 2 courses. There is also a french drain which is very important so water pressure doesnt build up behind the wall.


This wall was required in order to pass code in my county. Prior to that the homebuilder made a wall very similar to yours. It probably wouldnt have lasted long before rot took over. Luckily I didnt have to pay for the stone one!!!


I did, however, build a second wall, and the blocks ended up being ~$6.00 a piece for 16"x8" blocks.

Feel free to PM me if you have any questions

 

[KennyG]

Whatever you do, the most important thing is to get some drainage behind the wall so you don't have hydraulic pressure. I would suggest excavating an additional 6 " to 1 foot, cover the exposed dirt surface with landscape cloth, put a drain tile at the bottom and then backfill behind the wall with gravel. Cinder blocks are not as good as landscaping blocks that have a lip on the back to prevent sliding, but they will probably work fine considering how low your wall is.

 

[Wakey]

I finally got back to this!

Today I will dig in a couple deadmen and after that comes gravel and the drain.

Thanks for all the advice!

 

[beeforty]

Have you thought about putting a gutter across the back and running the drains out front? It looks like you have a shed roof that dumps all the water to the back side, might help some to get rid of standing water back there and along the sides.