Extensible shells and related methods for constructing a ductile support pier

1. A method for constructing a ductile support pier in ground, the method qcomprising:

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 having an end closed by a cap;

inserting a driving mandrel into the shell, the driving mandrel further comprising a removable driving collar for using in driving the nested extensible shell, and a removable pin;

driving the shell into the ground using the driving mandrel;

removing the driving collar and continuing to drive the mandrel such that the shell cap is removed;

filling the shell with granular construction material;

compacting the granular construction material such that a bottom bulb is formed beneath the shell as driven into the ground;

raising the mandrel out of the shell while simultaneously adding additional granular construction material to fill the shell and form a ductile pier.

2. The method of claim 1 , wherein the cap of the extensible shell is integral to the shell.

3. The method of claim 1 , wherein the cap of the extensible shell is removable.