Method and device for mixing stabilizing chemicals into earthen formations

Claim 1

An in-situ mixing device for introducing and mixing hydroxy-aluminum into quick clay formations comprising: a helical blade having convolutions of at least one revolution and having a central opening therethrough, said convolutions having substantial thickness adjacent said central opening and tapering to an outer edge; a hollow torque tube having one end inserted through said central opening of said helical blade and fixedly connected therein; exit ports in said torque tube; means for pumping the hydroxy-aluminum through the hollow torque tube, out the exit ports and into the formation; means connecting said pumping means to the upper end of said torque tube; means for rotating said torque tube; means for controlling the vertical travel speed of said torque tube; means for rotating the helical blade at a speed different than thread speed; and bypass channels in the convolutions of said helical blade to permit flow of material thorugh said helical blade when said helical blade is rotated in the formation.

Claim 3

A method for infusing a hydroxy-aluminum mixture into a quick clay formation by means of an in-situ mixing device, comprising the steps of: (a) rotating a hollow torque tube with a helical blade having convolutions of at least one revolution attached thereto down into the formation, said convolutions having substantial thickness adjacent said torque tube and tapering to an outer edge; (b) creating a disturbed column in the formation and flowing the hydroxy-aluminum down the torque tube to the helical blade and into the formation; (c) rotating said torque tube and helical blade in place thereby mixing the hydroxy-aluminum into the formation; (d) rotating out said helical blade from the formation and allowing the formation to stabilize; and (e) permitting backflow through bypass channels in the convolutions of said helical blade.

Claim 4

A method for infusing a hydroxy-aluminum mixture into a quick clay formation by means of an in-situ mixing device, comprising the steps of: (a) rotating a hollow torque tube with a helical blade having convolutions of at least one revolution attached thereto down into the formation, said convolutions having substantial thickness adjacent said torque tube and tapering to an outer edge; (b) creating a disturbed column in the formation and flowing the hydroxy-aluminum down the torque tube to the helical blade and into the formation; (c) rotating said torque tube and helical blade in place thereby mixing the hydroxy-aluminum into the formation; (d) rotating out said helical blade from the formation and allowing the formation to stabilize; and (e) permitting backflow through bypass channels in the convolutions of said helical blade.