I had this come up a couple of years ago, and I simply used weldable rebar,
and welded dowels around the inside perimeter of the pipe.
From: George Ghaly [mailto:George.Ghaly(--nospam--at)parsons.com]
Sent: Tuesday, February 08, 2000 7:31 AM
Subject: Tension Reinforcement for Piles
Usually for concrete augered piles, tension (uplift ) is transferred from
pile cap to
the pile using reinforcing bar in the center that extend the entire length
of each pile.
What is the best way to transfer tension to concrete filled (steel pipe)