Form handling system

Abstract

A system is described whereby a large elongated monolithic conduit is formed within an excavation of a single continuous pour of concrete. The open core of the conduit is formed by an interconnected group of tubular form members, forming a static line within the excavation. The system includes a slipform mechanism that is progressively moved along the static line, molding wet concrete about the inner form sections. Successive inner form sections are disconnected from the rearward end of the static line (after the adjacent formed concrete has hardened), reduced in cross-sectional dimension, and transported forwardly through the static line to a forward conduit end. There the individual sections are expanded, cleaned and reattached to the front of the line as the slipform moves along. The successive inner form sections are disconnected, moved forwardly and re-expanded by a self-steering wheel supported transporter. The transporter is powered to move longitudinally within the static line. A trimmer is also provided at a forward end of the slipform to prepare a final grade within the excavation just prior to molding of the wet concrete.