ruslindsey(R&D Helical Piers)
company name that has this patent is Turbopier Industries
a division of Precision Pier USA,Inc.
Contact person:Engineer Stan Rupiper Phone#530-525-4560
Contact person:Sales Mike Lugwig Phone#303-901-1579
I'm sorry for the delay.
ruslindsey(R&D Helical Piers)
In reponse to the use of grouting with helical piers,
there is a company that has a patent on this.
the results are outstanding,also they have a patent
for attaching piers to rock.