uplift on precast piles

huangyhg

uplift on precast piles
any suggested details for developing uplift with precast piles?  i have seen proprietary products for tension splices, but have not seen similar details for developing the uplift with a pile cap.  we will be using a styandard 14" square precat pile.   
there are several ways to do it.  one of the better ones is to cast an insert into the center of the pile and then use a large shoe to drive the pile so you don't damage the entrance to the insert.  then epoxy a rod in there with a nut and plate on top to be cast into your cap.
i must say, though, if you have large amounts of uplift (something i deal with often), drilled shafts are the way to go.  it's pretty easy to construct something that can develop tension in your reinforcement with them.