System and method for installing an aggregate pier

A system for installing an aggregate pier in a soil matrix, the system comprising:

• a pipe extending along a pipe axis between a distal end and a proximal end, wherein an area of the pipe remote from the distal end of the pipe is configured to interface with a torque driver for rotating the pipe about the pipe axis, the pipe being rotatable in a first direction about the pipe axis, and the pipe being rotatable in a second direction about the pipe axis, the second direction being opposite the first direction,
• an end cap slidably disposed within the distal end of the pipe, wherein the pipe has a first configuration closing the distal end of the pipe and a second configuration wherein the distal end of the pipe is open, the first configuration and the second configuration defined by the location of the end cap with respect to the pipe;
• and,
• a helix disposed on the pipe between the proximal end and the distal end, the helix extending along at least a portion of an outer surface of the pipe, the helix extending radially from the pipe axis between the outer surface of the pipe to an outer edge of the helix, the helix configured such that when the helix is received in the soil matrix and the pipe is rotated in the first direction the helix imparts an axial force on the pipe in the direction of the distal end of the pipe thereby advancing the pipe into the soil matrix and transitioning the end cap into the first configuration, and the helix further configured such that when the helix is received in a soil matrix and the pipe is rotated in the second direction the helix imparts an axial force on the pipe in the direction of the proximal end of the pipe thereby withdrawing the pipe from the soil matrix and transitioning the end cap to the second configuration.