Earth anchors and methods for their use

An earth anchor comprising:

• an elongate hub having a trailing end and a leading end;
• and
• at least one blade attached to the hub;
• wherein the blade has a discontinuous circular periphery, wherein a continuous circle drawn around the periphery of the blade defines an area, wherein the blade has an area that is less than about 60% of the area of the circle, and wherein the ratio of a path of least resistance for the blade to the perimeter of the circle is greater than about 95%.

A method for inserting an earth anchor into the ground that contains expansive soils, the method comprising:

• providing an earth anchor comprising a hub having a trailing end, a leading end, at least one blade, and a lumen which terminates in a port above the blade;
• attaching tubular extensions to the hub, wherein the extensions are ported above the hub in one or more locations;
• inserting the leading end into the ground that contains expansive soils and rotating the earth anchor until the blade is moved a predetermined distance into the ground;
• and
• introducing a low strength, impermeable material into the lumen until the material exits the port and forms a mass filling the voids created by the path of the blades of the hub upon insertion into the ground;
• wherein the blade has a discontinuous circular periphery, wherein a continuous circle drawn around the periphery of the blade defines an area, wherein the blade has an area that is less than about 70% of the area of the circle, and wherein the ratio of a path of shear resistance for the blade to the perimeter of the circle is greater than about 90%, and further comprising attaching an extension to the trailing end of the hub.