Apparatus for inserting prefabricated vertical drains into the earth

Abstract

Apparatus for inserting an elongated flexible prefabricated vertical (PV) drain downwardly into the earth. The apparatus includes a vertical mast having a lower standard mast base and a lightweight extra long mast extension. A vehicle supports the mast from its mast base in order to raise and lower the mast to and from vertical and to otherwise manipulate and transport the mast in a conventional manner. A longitudinal chamber extends for the entire length of the mast and carries therein an earth penetrating tube for vertical movement. This earth penetrating tube also has a passage therethrough for receiving the elongated flexible PV drain for movement with this insertion tube down into the earth when driven therein. The mast extension includes a series of axially aligned extension tubes constructed of light weight material and removably connected together end to end, and a combination spar and guy mechanism is utilized for supporting this long mast extension from the relatively short mast base. The elongated flexible PV drain is fed up the mast through a feed tube, over the top of the mast and back down through the internal passage of this earth penetrating tube. This entire combined passage way is made substantially air tight so that a feed line may be blown therethrough with compressed air assistance in order to provide a feed line for pulling a new elongated flexible PV drain through the passage.