Pile Supported Wall - Foundation Engieering by Peck Hanson Thornburn 4

[CWEngineer]

I am using the Pile Supported Retaining Wall Example on Page 436 as a reference for a problem that I am working on.

Here are the loads I have about point A:
Sum V = 13.16 k
Sum H = 9.39 k
Sum M About Point A = 176.55 k-ft clockwise, (I have water pressures). With this type of loading my vertical resultant is near the edge of the toe, but still within the footing.

I am following the same pile layout right now, except I am using 5.5 ft spacing instead of 3 feet.

When I calculate the Vertical Components of Pile Reaction, I get a positive value for Row 1, a positive value for Row 2. BUT I get a negative value for Row 3.

Do you guys know what this negative value means? Also do you guys have an idea of what I can do to make this value positive?

THANKS

 

[CWEngineer]

Thanks chichuck,

I still have not been able to find a pile supported retaining wall with one pile instead of multiple piles. Appreciate your help if you can point me in the right direction.

Thanks
gman1

 

[CWEngineer]

Hi,

I had another,hopefully quick question. On this example Row 3 is 21k in compression. Say if instead Row 3 came out to be negative (tension), would that mean that I would have draw the line for Row 3 going down 21k on the diagram and then continue drawing three more lines at angle upward which would now add to -21k + 21.9K +22.7K + 22.7K = 46.3K, which indicates that SumV would have to be 46.3k on a 6' strip?

THANKS
gman1