Extensible shells and related methods for constructing a ductile support pier
Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.
1 . A system for installing ductile support piers in ground, the system comprising:
an extensible shell for constructing a ductile support pier in ground, the extensible shell defining an interior for holding granular construction material and defining a first end having a first opening therethrough for receiving the granular construction material into the interior and an opposing second end closed by a cap; a removable driving collar and,
a driving mandrel configured to nest in the extensible shell, the driving mandrel further comprising a pressurized mandrel delivery system for constructing a bottom bulb below the second end of the extensible shell.
2 . The system according to claim 1 , wherein the driving collar is reversibly affixed to the driving mandrel by a pin.
3 . The system according to claim 2 , wherein the pin is threaded.
4 . The system according to claim 1 , wherein the driving mandrel includes a driving plate.
5 . The system according to claim 1 , wherein the driving mandrel includes a bolt-on connector.
6 . The system according to claim 1 , wherein the extensible shell is constructed of modular sections.
7 . The system according to claim 1 , wherein the driving mandrel is provided with flow ports in a mandrel bottom.
8 . The system according to claim 1 , wherein the cap is removable.
9 . A method for constructing a ductile support pier in ground, comprising:
positioning an extensible shell for driving into ground, the shell defining an interior for holding granular construction material and defining a first end having a first opening therethrough for receiving the granular construction material into the interior and an opposing second end closed by a cap;
inserting a driving mandrel into the shell, the driving mandrel further comprising a pressurized mandrel delivery system; using a removable driving collar attached to the mandrel for driving the extensible shell into the ground
driving the shell into the ground using the driving mandrel;
filling the mandrel with granular construction material;
flowing the granular construction material using the pressurized mandrel delivery system such that a bottom bulb is formed beneath the shell as driven into the ground; and,
forming a ductile support pier by raising the mandrel and simultaneously adding granular construction material to fill the extensible shell.
10 . The method according to claim 9 , further comprising attaching the driving collar to the mandrel using a pin.
11 . The method according to claim 9 , further comprising using a driving hammer to drive the drive collar for driving the extensible shell into the ground.
12 . The method according to claim 9 , further comprising installing the extensible shell in modular sections.
13 . The method according to claim 9 , further comprising removing the driving collar after driving the shell into the ground.
14 . The method according to claim 13 , further comprising continuing to drive the mandrel such that the cap is removed.