Method of centrifugally forming a subterranean soil-cement casing

A method for centrifugally forming a subterranean, cylindrically shaped soil-cement casing in material located in a subterranean earth situs, comprising the steps:

• advancing and rotating a soil processing tool into said situs to break said material into pieces, said soil processing tool forming a hole as it advances;
• while advancing said soil processing tool into said situs, introducing a cement slurry into said pieces from said tool at a velocity sufficient to hydraulically divide said pieces into particles and mix said cement slurry with said particles to form a soil-cement slurry, said soil-cement slurry containing cementitious solids, soil particles and free water;
• withdrawing said soil processing tool from said situs;
• while withdrawing said soil processing tool, rotating said tool at a rotational speed to exert a centrifugal force by said tool upon said soil-cement slurry in excess of two G's, whereby said centrifugal force causes the solids of said soil-cement slurry to migrate further from the center of said hole than said free water to form a first cylindrical region at the outer edges of said hole and a second cylindrical region at the center of said hole, said first region having a smaller proportion of free water than said second region;
• and
• allowing said mixture in said hole to set up.