You should contact Mueser Rutledge Consulting engineers. They were the geotechnical engineers for the WTC Slurry wall systems and are currently involved with the remedial work underway Their web site is :www.mrce.com
Mark Montgomery
deep foundations contractors inc.
Thornhill On Canada...
Scot The best possible option would be to install mini piles eith beside or through the existing drilled pier. Mini (or micro or pin ) piles can be installed around the perimeter. they are capable of taking loads in the order of serveral hundred kips in both tension and compression. You can look...
