Stability of Vertical Excavation 1

[StrLamp]

I have a quick query regarding the vertical excavation of the soil. Nowadays, our city has issued a new advisory stating that any excavation occurring within 10 feet of the property line needs to be reviewed by a P.Eng. In the urban setting, due to the limited space up to the property line, the city always asks for excavation and shoring review. Installing a soldier pile is a viable option from a technical perspective. However, the cost and specialty required by local contractors are causing homeowners to avoid choosing this option. Another option is sloped excavation. I have been proposing sloped excavation as shown in the attached screenshot. I have noted that this excavation is only applicable for type 2 or type 3 soil or better, to be confirmed by a geotechnical engineer. The city was approving this option so far. Out of nowhere, the city is now asking for either slope stability or shoring design (soldier pile). A soldier pile is not an option for a client as it is intended for two-story residential construction and it has to be installed on three sides (due to cost and the tight space for installation). Note: this excavation is not encroaching on any angle of repose of the neighboring properties.

I am considering conducting a slope stability analysis. The biggest challenge I've found is that the correct properties of the soil, as in unsaturated soil, have both residual and fully softened properties. Can any geotechnical engineer please advise me if this excavation can retain itself? If I go with a slope stability analysis, which route do you recommend for me? I mean the references and software. Thanks a lot.

 

[phamENG]

If I go with a slope stability analysis, which route do you recommend for me?

I'd recommend you hire a geotechnical engineer. Determining soil properties and doing slope stability calculations are part of their job, after all.

 

[HTURKAK]

We cannot say if the excavation can retain itself without knowing site info. and soil data . But i will suggest you to look to the following doc. and prepare your own excell spread sheet for slope stability.

U.S. Army Corps of Engineers Slope Stability EM_1110-2-1902

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He is like a man building a house, who dug deep and laid the foundation on the rock. And when the flood arose, the stream beat vehemently against that house, and could not shake it, for it was founded on the rock..

Luke 6:48

 

[HTURKAK]

I have attached the other useful doc.
The following doc. U.S. Army Corps of Engineers Slope Stability EM_1110-2-1902
..

He is like a man building a house, who dug deep and laid the foundation on the rock. And when the flood arose, the stream beat vehemently against that house, and could not shake it, for it was founded on the rock..

Luke 6:48