Abstract: A system for forming a vertical structure through the incremental pouring of wet concrete has a plurality of vertical columns external to the concrete of the vertical structure; a slip form structure comprising a pair of opposing walls forming a bottomless trough; a main frame coupled to the slip form structure, wherein the main frame is supported on, and configured to move vertically along, the vertical columns; and a work platform residing below the slip form structure and main frame, the work platform being supported on, and configured to move vertically along, the vertical columns; wherein the main platform moves independently of the work platform.

Abstract: A system for forming a vertical structure through the incremental pouring of wet concrete has a plurality of vertical columns external to the concrete of the vertical structure; a slip form structure comprising a pair of opposing walls forming a bottomless trough; a main frame coupled to the slip form structure, wherein the main frame is supported on, and configured to move vertically along, the vertical columns; and a work platform residing below the slip form structure and main frame, the work platform being supported on, and configured to move vertically along, the vertical columns; wherein the main platform moves independently of the work platform.