How to Build a Retaining Wall and 6 Reasons they Fail

today we're gonna cover six big mistakes when you're building a retaining wall and how to avoid them so let's get this wall would fail over a year ago in this exact spot in this exact way you can see where the grades behind this wall have dipped down it's gonna blow that wall out in fact we had one catastrophic wall failure on this project last year we had to repair it we got another one coming up it's not because I have a crystal ball it's because the writing was on the wall it's just completely shot right there that's from draining from not maintaining it you can see where all the grades have dropped down in here now we've got big sinkholes behind this retaining wall I can literally stick my leg down in here up to my knee you can see the distinct angle all bowed out this problem could have easily been avoided had the property owners the development company listened when I screamed my head off all you need to do is either a raise the height of the retaining wall up just tall enough to direct the water that's coming down from the other property away from this one spot and divert it back onto their own property or be create a berm above the retaining wall which keeps the water from funneling into this location two simple fixes not done in time retaining walls come in all shapes and sizes some of the absolute strongest retaining walls made are actually poured retaining wall to remove a retaining wall like this we're gonna be outfitting the front of this skid loader with a jackhammer and pounding in the front just to soften up the concrete why is this wall so strong well it's how it's designed it's one continuous element this has the lateral footing down at the base of the soil keeping the retaining wall from tipping over it's all about the base they don't build if you're building a retaining wall today you make sure that you design the retaining fault wall for the exact type of material that is going to be on the face that means if it's a modular block retaining wall you gotta have the right drainage to have the right geo for it if you're using a bull the retaining wall you got to have the right size stones it doesn't matter what material you build a retaining wall out of you've got to design it to withstand the elements this is a great example there's another typical problem with retaining walls people rely on the drain tile to actually function the wall behind me it looks okay but it's actually in a state of failure the first sign that it's in a state of failure is if you look at the base of the wall you can actually see where the drain tile opening has water percolating through that means that the water in this entire retaining wall is concentrated into that drain tile system that's just a four inch perforated drain tile it's not meant to handle large amounts of water it's meant to only act as an emergency overflow at best the entire retaining wall should allow water to pass through evenly meaning the water and the behind the retaining wall should never get down to the drain tile system if you see water pumping through a drain tile opening that means that entire wall is in a state of failure all of the drainage aggregate is bound up behind me is a small portion of a 30-plus thousand square-foot retaining wall we've built over a decade ago now even though this company davell invested millions of dollars into the infrastructure of this property they failed at one important component and that's maintaining their retaining walls it's the most important and easily up kept thing that you can do on a retaining wall is to make sure that the grades stay flush behind the back to the block this is a great example of what happens when you allow the grades to fall behind the wall they're going to find cavities I can reach in and put my whole hand inside this cavity behind this retaining wall and you can see other cavities and that's gonna create premature failure and you're in this retaining wall oftentimes I see retaining walls massive ones like this get neglected when that neglect sets in failure will rapidly occur so what you can see is they've actually allowed the vegetation to grow right through the face of the retaining wall that's how far the neglect has gotten on this site what happens when that vegetation grows through is it creates gaps in the blocks as the plants grow their roots expand and that creates spacing in the blocks that spacing is a cavity for the aggregate behind it to flow right through the face of the retaining wall that also creates funnel points where the water's gonna want to migrate instead of dispersing evenly behind the retaining wall it's now I'm gonna find a spot and it's gonna puncture through that retaining wall creating potential issues during heavy rainstorms here's another great rule of thumb that you can use on almost any retaining wall you want to plant a major tree Bush or shrub on out like the pine tree you see behind me take the height of the retaining wall now in this case it's just a five footer but multiply it by two so that means to take the height of the wall five feet times two that means you go ten feet behind that retaining wall before you would plant this tree if you plant it too close to the wall what happens is as the tree grows up it creates undue stress and that's called a surcharge on to the retaining wall itself so as the trees going up the roots are growing down it's gonna push that wall out but if you use that rule of thumb that should put you safely outside of the surcharge zone of most structural retaining walls here's another myth for yuppie rock or sand makes great battlefield material nothing could actually be further from the truth especially in the drainage zone you want a dedicated material that is a velar in nature can lock together it doesn't have a lot of fine sort of choice I use this three-quarter inch here try the reason that it's important is because it's water flows through it and through the face of the wall it's not going to move and can refit all types a broad movement behind the wall and not transfer that into the actual base today we covered six issues that typically make retaining walls fall apart but sadly there's a lot more reasons why they fail let me know in the comments down below if there's any specific videos that you guys and gals would like to see god bless and go get them [Music]

Channel: Stanley "Dirt Monkey" Genadek

Views: 491,418

Keywords: Retaining Wall, Retaining Wall Failure, how to build a retaining wall, retaining wall construction, retaining wall diy, how to, how to install a retaining wall, retaining wall installation, landscape retaining wall, how not to build a retaining wall, why retaining walls fail, do it yourself retaining wall, diy retaining wall, how to retaining wall, retaining wall ideas, retaining wall repair, stone retaining wall, brick retaining wall, natural

Id: XZUXxoZ1n04

Length: 6min 44sec (404 seconds)

Published: Fri Oct 07 2016