Two sided Soldier Pile Lagging Wall

[nova5852003]

I am working on a project where a soldier pile lagging wall is used to retain earth at a stageline. In the first stage the lagging is installed traditionally as the excavation progresses down. Once the work here is completed, the excavation is then backfilled and the second stage of excavation begins on the opposite side of the solder pile and lagging. What are my options for installing the lagging a single time for use in both stages? Anyone have any good details or economical ideas?

ps sheet pile is not an option due to numerous utility conflicts

 

[DaveAtkins]

If you use steel H-piles for your soldier piles, you could weld plates on each side of the web, creating a slot for the timber lagging to slide down inside. For the first excavation, the lagging would bear on the flanges. For the second excavation, the lagging would bear on the plates.

 

[EireChch]

I dont see why it couldnt be used for both, just need to make sure its properly fixed to the king posts. All in the connection detail.

 

[jayrod12]

I would be adding wood blocking between the flange and the lagging during the second excavation, or a steel appendage akin DaveAtkins suggestion. Depending on how critical it is on the first side, you could potentially just let the lagging move from the one side of the HP to the other while they're excavating. But I'll admit that I'm only proposing that last option because it's an online forum and it's not my project. That one is a bit dicey.

 

[MTSOE]

For Stage 1, I would expose the entire pile web (without disturbing the soil/fill behind the outside of the back flange) and install the lagging against the inside face of the back flange. A piece of steel angle could then be welded to the web of the pile to sandwich the lagging in place. The same lagging could be exposed on the other side for Stage 2.

 

[PEinc]

In your first stage, when you install the wood lagging, block it (with short, cut off pieces of lagging) snuggly to the rear flanges of the soldier beams. Note that this can reduce the lateral support of the soldier beam and adversely affect the allowable bending stress of the beams. When you make your excavation for the second stage, the lagging will be in the proper position. Install the blocking in the first stage so that the lagging does not fall out when digging for the second stage.