Method for making multiple-part concrete pole
This invention relates to pole structures used for supporting transmission and distribution lines, lighting and communications systems, highway signs, traffic signals, and the like. More specifically, this invention relates to a new and useful design of a multi-sectioned pole, with at least one telescoping upper section made of metal or another similar lightweight material and a base section composed of concrete or similar material that can be directly embedded into the ground without the need for baseplate-type foundations, or other preparatory work.
1. A method for forming a concrete pole comprising the steps of:
placing a plurality of first elongated reinforcing strands into a mold defining an upper end and a lower end and an axis, and tying said first elongated reinforcing strands to a first spiral strand surrounding the first elongated reinforcing strands;
inserting a first charge of wet concrete into said mold;
spinning said mold about its axis thereby slinging said concrete outwardly to form a compact outer wall with a hollow interior;
stopping the spinning and measuring the wall thickness;
adding additional wet concrete into said hollow interior; and
spinning said mold about its axis again.
2. A method for forming a concrete pole as recited in claim 1 , and further comprising the step of placing a plurality of second elongated reinforcing strands into said mold outside the first plurality of strands and tying said second elongated reinforcing strands to a second spiral strand surrounding the second elongated reinforcing strands prior to inserting said first charge of wet concrete into said mold.
3. A method for forming a concrete pole as recited in claim 2 , and further comprising the step of tensioning some of said strands prior to spinning said mold.
4. A method for forming a concrete pole as recited in claim 3 , and further comprising the steps of encasing some of said elongated strands in casings for part of their length adjacent to the upper end of the mold prior to inserting the wet concrete; allowing said wet concrete to dry after said spinning again; and tensioning said encased elongated strands after said wet concrete has dried.