3 Sided Sheet Pile Wall

[RFreund]

This was discussed some time ago and I'm wondering if there is a method out there that other have used. My original thinking was similar to what the previous OP had suggested.

http://www.eng-tips.com/viewthread.cfm?qid=358645

The question is: If you have a sheet pile wall that is not a complete box. Say that it is set into a slope. So you have a long backside then you have two shorter side walls. The long back wall has a waler which spans between the two side walls. There is a reaction now placed on to the side walls. How do you calculate the resistance to this reaction of the side walls?

Thanks!

EIT

http://www.HowToEngineer.com

 

[RFreund]

I'm actually a little confused as the previous OP had said that they used the shear strength x the contact area.

Did they mean cohesion or what did they use for a normal force?

EIT

http://www.HowToEngineer.com

 

[WinelandV]

Since you have the waler already, I would try to support the waler at each end of the long back wall independently of the side walls - soil nail into the retained section or knee brace back into the excavation - and not rely on any strength from the sidewalls. It's been a while, but if memory serves, the interlocking between the sheets may not be up for passing that load into your side walls. Also, the load path from the waler into the side walls isn't clear to me, short of welding/bolting a bracket to the sheets (but this brings its own local connection issues). If you absolutely need to, perhaps the sheet manufacturer has info and/or recommendations for transferring this force into the sidewalls.

 

[RFreund]

I understand the desire to avoid this but it does seem like a rather good question of why not?

If you utilized walers to distribute the reaction you really would not need to rely on any shear transfer of the interlock assuming each sheet acts individually (atleast I don't think you would).

I guess this problem stated another way:
How could you quantify the resistance of sheet piling used as a deadman. However the sheet piling parallel to the load. For example if you have a cantilever sheet pile wall and you "T" into the back of the wall. You then have walers to connect the sheeting. So now how would you find the capacity of the stem of the "T" to act as a "deadman"?

Maybe the answer to both of these is you don't!
But they both seem like they could work.


EIT

http://www.HowToEngineer.com

 

[RFreund]

Apparently this issue is addressed The Recommendations of the Committee for Waterfront Structures, Harbors and Waterways EAU here:

according to:
Assessing U.S. practices for waterfront steel sheet pile walls by Michael J. Garlich w/ Collins Engineering in Chicago, hmmm, I might know him....

http://www.porttechnology.org/images/uploads/technical_papers/PT46-12.pdf

EIT

http://www.HowToEngineer.com

 

[GeoPaveTraffic]

I've done a couple of short term shoring project that were three sided. All worked out fine, but as stated in the other post on this topic, never really performed what could be called a rigorous analysis.

The way I looked at it was to take the load from the "back" wall into the wales along the side walls. Then I specified welds between the wales and each sheet to transfer the load to the sheetpiles. These were Z sheets, so it was easy in my mind to justify load transfer from the sheetpiles to the soil on the side walls. I looked at the average stress needed along the side walls (just the portion that was in the ground). As I recall the average stress was very low, so it was easy to say that the condition was ok by judgement.

I'm going to take a look at the above link to see what that method recommends.

Anyway, that is my two cents worth.

Mike Lambert