<p>A STEEL PIPE PILE (1) INCLUDES A STRAIGHT PORTION (8) HAVING A CYLINDRICAL SHAPE; AND A TAPERED PORTION (4) THAT CONTINUES TO AN END OF THE STRAIGHT PORTION (8) AND AN OUTSIDE DIAMETER AND AN INSIDE DIAMETER THEREOF REDUCE AWAY FROM THE END, WHEREIN A RATIO OF LENGTH TO DIAMETER H1/D1 IN WHICH A LENGTH H1 BETWEEN A LARGE END AND A SMALL END OF THE TAPERED PORTION (4) IS DIVIDED BY AN OUTSIDE DIAMETER D1 OF THE LARGE END IS 0.1 TO 2.5.</p>
