Proposed Excavation Shoring

[Daca02]

Does anyone with more experience see any problems with the box excavation shoring configuration? (4' vertical and horizontal spacing between cross braces. All material is lumber)/

My calculations show the 3x10 horizontal lagging, 3x10 uprights and 4x4 braces should be OK. The only issue I have is that research I've done online most lumber shoring use upright planks for the "sheathing" or a soldier pile and lagging design.

 

[JedClampett]

It's super inappropriate for us to comment on a shoring scheme without knowing the soil properties. This work is done by specialists and sealed by them. Working in shored excavations is dangerous and people die in them.

 

[Daca02]

Sorry, its Soil type B. Mostly sand. The water table is about 2' from the bottom but it will be dewatered when they are excavating.

 

[thaidavid40]

A 4x4 seems pretty skinny for a 16'-deep cut.

Thaidavid

 

[SlideRuleEra]

Daca02 - This shoring is so heavily loaded that simple loading assumptions have too much room for error. More information is needed on soil properties, lumber details (dressed or rough cut - wood species, grade and condition), dewatering (inside excavation only, or general surrounding area), any activities or loading on the ground surface adjacent to the shoring (surcharge), etc. Suggest having the plan evaluated and sealed by an experienced engineer.

IMHO... I don't like the plan at all:

1. The interior is too cluttered with braces.

2. Every (heavily loaded) member has to perform as expected. Just one member failing could be a problem.

3. The 3x10 verticals are not properly proportioned, they are "too thin". Accidental impact or horizontal loading (shown in red on the image below) could cause the vertical member to rotate... initiating a collapse. Even doubling the 3x10s (to make more or less a 6x10... not for strength, but for stability) is marginal.

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