Anchored Pile Wall with MSE Wall Above 2

[HSRYAN7]

Hey everyone,

I am looking at a scenario where an MSE Wall will be placed above an Anchored Soldier Pile Wall. I'm designing the anchored pile wall and need to determine the anchor loads, pile section, etc.

I'm having trouble determining the interaction between these two different wall types and what the best way to analyze this scenario is. The MSE Wall designer has given me a maximum uniform bearing pressure from the wall to use in my design. Right now my plan is to model a horizontal ground line and apply the loads from the reinforced fill and retained soil as surcharges and run it as a boussinesq analysis. See attachment for a sketch.

Is this the best way to analyze this scenario? Is there anything I am not taking into account that I should be? I am aware that there is a strain compatibility issue between the MSE wall and anchored pile wall but I am thinking that a big enough offset of the MSE wall from the back of the soldier pile wall will alleviate that issue.

Any help would be much appreicated!

 

[EireChch]

Moving the MSE wall back a few meters wont alleviate it, it will still load the wall. The more you move it back the more space you loose.

But I think you approach is reasonable, carry out all the checks on wall stability etc, consider your worst credible soil properties and ground water conditions. Check for global stability.

There will be minimal deflection of the wall since it is anchored, and even if there is more deflection than anticipated, im sure it can be accommodated in the MSE wall.

 

[PEinc]

I designed a similar wall. The anchored wall had a temporary height of up to 28 feet with an MSE wall directly behind the anchored wall. The MSE wall has a height of up to 33.33 feet on top of the anchored wall. The MSE wall has big facing blocks with geogrids. I got the actual bearing pressure distribution under the MSE wall from the MSE wall designer and applied it as a vertical surcharge to the anchored wall. The anchored wall's finished height was 24 feet. It used double WF soldier beams at 4' on center with one and two tiers of tieback anchors. Remember, the surcharge from the MSE wall is greater than just the uniform dead load of the wall. As the MSE wall wants to resist overturning, the bearing pressure at its toe (which will load the anchored wall) will be higher than a uniform dead load. My job had an MSE wall bearing pressure of up to 5,325 psf, significantly higher than the wall's uniform dead load.

See the picture below. The anchored wall has a shotcrete facing over the "temporary" timber lagging. The beige wall above the shotcrete is the MSE block facing.

http://www.PeirceEngineering.com

 

[EireChch]

Pink star PEinc

 

[geomane]

Nice work PEinc

 

[PEinc]

Thank you. Much appreciated.

http://www.PeirceEngineering.com