A slip-mold having a housing having (a) concrete hopper having (b) means for distribution of quick set concrete within said hopper, (c) a mold cavity, and (d) at least one tunnel, in communication with said mold cavity, and extending through said housing from the leading to the trailing end of said housing. The tunnel through the housing is of sufficient height and width, and positioned within said mold housing, to permit rebars, extending from an iron work array, to pass through said mold cavity without becoming embedded in concrete, concurrent with the formation of a slip formed concrete structure on a portion of said iron work array.