Abstract: A method of strengthening and improving the load-bearing capacity of soft clay-containing subterranean soil comprising advancing a soil processing tool into said subterranean soil to break said soil into discrete particles; while advancing said soil processing tool into said soil, introducing an aqueous composition consisting essentially of water and a clay dispersant in an amount sufficient to disperse said discrete particles and make water from said clay available for hydration of subsequently added cement; when the soil processing tool has reached its desired depth, withdrawing same and simultaneously adding during said withdrawal a cementitious composition comprising water and a cement in a water-to-cement weight ratio of 0.4 to 1:1 and in an amount which provides a weight ratio of the total water of said aqueous dispersant containing composition, said clay soil and said cementitious composition to said cement of about 4 to 6:1; and allowing said mixture to harden.