Retaining wall BASE failure

yep that is that is the stuff that will break the handles on your shovel oh he's getting out of the exavator does that blood on your [Music] hand first day on the First wall of the Year problems [Music] all right guys we're going to back this up to one of the very first jobs of the Season where things go from bad to worse to really bad and then we get that all fixed and repaired and then things go pretty smooth and then they get bad again this is uh first job of the Year kind of second we did one in what March and then we had another little blast of winter we're coming off this wall here 15 ft then the stairs and then the stairs and then it will come back out again and just kind of return up are we going up the hill or yeah up the hill [Music] okay first day on the First wall of the Year problems stomp around on that problem we got ourselves on water bad here so sumping up moisture only way to fix it is oversized like we did but uh we're going to have to go a little thicker Rock to bridge this where's one of those staks you can't really see how it's like walking on a water bed we thought 8 in of rock was going to bridge it and it did not all right we ready yeah push we in there yep soil correction time no resistance what that's crazy it's always something it's always something so when we encounter soils like this we have two types of soil Corrections that we can really go to that we've used successfully time and time again one is called a full-fledged soil correction and that's where we excavate all the way down and remove all of the compromised soils and then we have to do it in an oversized fashion so if our wall is right here for every foot we go down we have to go out a foot and we have to create a bridge or a pyramid up to the base of that retaining wall and then from there we we can then rebuild we put new good structural fill soil back in place it and compact it that's what we call a full-fledged soil correction the other option that we've used successfully time and time again is a bridging soil correction and that's where will dig down and then what we'll do is we'll use Rock but then we stick geogrid inside of that rock so instead of having 6 in of rock below the retaining wall we may have 1 to 3 feet of rock below that retaining wall and then that layers of rock are fortified with geogrid mixed all the way throughout we've actually done bridged retaining we've done bridged soil Corrections for Habitat for Humanity in some of the worst conditions you can possibly imagine they wanted to build a row of houses right up next to a swamp and we're talking about a swamp where if you walked in it you got stuck and what we did is the bridging soil correction per engineering requirements and that wall is still holding today this was a wall hundreds of feet long and five or six foot tall so we know that it works we're using principles that we've taken from Engineers these aren't things we've created these are situations we've been in that geotechnical Engineers have said do this don't do that and then we just bring that experience with us into these residential job sites and that's what we're going to be doing today is a bridging soil correction yeah so we're going to have good 18 in I think we're going to do a foot rip wrap here you got to tell them what rip wrap is 6 in of so 3-in rip wrap and then some uh and 6 in of this 3/4 to base on and that should uh hopefully Bridge it up a little better we're going to hand dig it because the other part of this is that bank might collapse if we bring the minia ex down through here to get it where we need to dig this out we only this section is beefed up just it's just yeah this what is that like four four ft just this little chunk in between the lines I think it's been years of this gutter right here um bad drainage it just goes right down the side and sits down in here and turns all the sup oh absolutely well they got that drain spout right around the corner too that's shooting right to there and coming down right here so when this dries up it's going to obviously get better sure is pretty piss bar right here yep that is that is the stuff that will break the handles on your shovel [Music] okay so it's been quite a day here we dug down found some really unstable soils did a little soil correction and it didn't Bridge it up so we had decided to go deeper and wider with our soil Corrections and um upon doing that I found the septic line not too deep under here so that was right where our wall was going to go so what's the chances I want to know what the chances are of us not hitting that with three dudes throwing shovels under there digging it out we didn't hit it remember how you're were saying plan ABC so we're going to move this everything forward so we got lucky here goes from wood siding to the the concrete panels go all the way up even behind this siding so we can still put our wall here so we get to move it forward out of a zone that can cause any damage to anything cuz putting the all that bridging that up the hoping it would not put too much pressure on that pipe would you know is not something you really want to cross your fingers rolling into dice yeah I don't want to roll the dice on cracking that so we're going to move it forward and that is Plan D dude I think we're on like Plan D by now I swear to God we got to be getting close to e all right so let's dive into the mind of Timmy for just a moment here he does not want to build that retaining wall right over the top of that pipe right there he doesn't mind moving that retaining wall North just a little bit and the reason is is right in that location even though a bridge soil correction would probably work just fine there's the potential for ground movement in Minnesota we go through what's called Freeze thaw Cycles multiple times a year and we get a lot of ground movement think of California but in slow motion instead of an earthquake hitting all at once in Minnesota our ground is constantly freezing thawing freezing thawing in a constant state of fluctuation and there's a lot of water right in that zone so although we could safely build the retaining wall Tim doesn't want to build a bridged retaining wall over a pipe which has to remain rigid because he doesn't want that ground to be moving and grooving underneath that rigid pipe and create a crack so he's just going to move that bridged soil correction north where there's less water less water means less likelihood to have a freeze thaw cycle he's still going to bridge it because he's not comfortable with the soils in that zone but he doesn't want to compromise the Integrity of that pipe that that we discovered underneath that area we can clean it up with the shovel too close is the name of the game we'll clean it the rest of the way up but it's good morning everybody another day another soil correction we hit a whole bunch of slap again video ain't going to do it justice so we were hoping with this being the higher elevation on our second on the second tier of our wall here was going to be drier cuz you know gravity but we did not get that lucky which is no big deal we're just going to go down a little bit deeper and BR it up with a little bit more r getting to about over here no it's got more resistance than over there that part sucks yeah still better than it was we're only getting about that much was like freaking 18 in oh he's getting out of the exavator all right you want to give her you want to give her a little test yeah that is that blood on your hand or is it paint paint harder that probably goes all the way down to the footing honestly it probably goes down under the footing that crappy there this stuff changed color that was where it got good was right right in there that's way better yeah yep oh yeah oh it's just kind of right the the lines are the fundamental difference between a complete soil correction and a bridged soil correction is the amount of excavation required to do each one a complete soil correction means you are removing everything down to nonorganic gray clay at least in our areas we call it gray clay and this is a firm solid material that H holds no organic material in it whatsoever and then you're re using soils or bringing in structural soil not necessarily Rock but structural soil to reinforce that area and that's what requires that on to one slope where a bridged soil correction on the other hand does not require complete removal of the material but you've got to get enough of that material removed so that you are fundamentally creating a bridge you are creating a a Zone a safe Zone to allow the material underne to move and groove but you've got this huge thick cushion of rock fortified with layers of grid that are taking all of this subground that's moving and grooving down here and this material just stays Rock Solid steady that's the fundamental difference between a bridge soil correction and a full-fledged soil correction all right well thanks for going along with us on this ride it was an interesting journey and I know some of you guys are probably looking at this thinking hey what about them down spots aren't those just going to ruin that retaining well again and this was one of the first jobs of the year and we didn't get a very good shot of what we did with that down spot but all of those gutters all that water all those down spots are directed away from that retaining wall sometimes we'll put on extensions but other times we'll bury a pipe and capture all of that water so that as it comes down the spout it's self-contained in that pipe it's not a perforated pipe it's a solid pipe that will run down and out and then daylight toward another part of the property so there's multiple options but one option that is not on the table is allowing that water to continue to migrate behind that retaining wall so that's it for this video hope you guys enjoyed the process and watching how we uh handle some unique challenges God bless you guys and go get them we'll catch you on another one we work around the Minnesota area so if you happen to be in this neck of the woods and want want to have us take a look at one of your retaining walls just give Tim a Call 612 715 3637