I would be interested in seeing a typical soil boring and the geotech report's recommended soil properties. What is the height of retained soil? Where is groundwater? Any surcharge loads behind the wall? Are you applying safety factor(s) to the soil properties or to the calculated embedment...
Not enough information given. WARNING: 8.5' excavation with an adjacent structure! Existing structure? Existing footing depth? Underpinning required?
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Rarely have I ever had to pre-load internal braces. However, see attached PDF.
www.PeirceEngineering.comhttps://files.engineering.com/getfile.aspx?folder=662eaf5f-d181-4d68-bca4-616074c26fb7&file=FHWA_Brace_Preloading.pdf
JohnnyB, can you ask the structural engineer for unfactored service loads instead of factored loads. You will need service loads if you need to calculate settlement. This is for a building, not a highway. IBC has a different ASD formula than AASHTO/FHWA.
Look for a download of FHWA-SA-97-070...
Geoluk, underpinning should not be done in multiple lifts (i.e., underpinning the underpinning). Underpinning in multiple lifts compounds the possibility of problems and settlement ( 2 lifts, double risk, 3 lifts, triple risk, etc.). Underpinning should be performed using hand excavation, not a...
Seems to me you need a written agreement from the neighbor stating the maximum future depth of any dredging. Then design your wall for that depth or maybe even deeper.
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I would not consider that a rubble stone wall. What is the condition of the brick wall that is sitting on the single layer of big stones? How thick is the concrete on top of the stones? I have had a couple of projects where the rubble stone wall was in such bad shape, we removed it in sections...
You apply the various driving forces (wind, live load, hydrostatic, seismic, etc.) to the structure with their appropriate, individual, load factors (LF > 1). When checking stability (overturning and sliding), one of the resisting forces is the dead load of the footing but, in LRFD design, you...
Remember, if you are doing LRFD design, you multiply different loads by different load factors that are greater than 1 and these factored loads give factored stresses that need to be less than the various material strengths multiplied by their particular resistance factors. The more homogeneous...
Diagram the wall and the forces - active soil pressure, passive soil pressure, live load and dead load surcharge pressures, and the building's shear force and moment. Then analyze for stability and bearing.
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I would expect tie rods connecting the foundations on two sides of the building to be a more economical, more typical solution for resisting outward lateral thrust.
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It seems like you are making this a lot more complicated than needed. If this is a design for a real project, you should be looking a cantilevered sheeting design methods and examples readily available in numerous publications. None of what you described is needed or used. If this is for some...