Means for forming structures of complex configuration

Claim 1

A form assembly for in-the-field casting of reinforced concrete drainage structures having an external face portion constituting a reentrant concavity of complex geometrical configuration in such structure, including an integral preshaped form liner member of generally concavoconvex configuration corresponding to such reentrant concavity of complex geometrical configuration in such structure, said integral preshaped form liner member having a front surface and a rear surface, said front surface forming such external face portion of the completed structure, a network of rod-like reinforcing members of generally concavoconvex overall configuration adapted to substantially encompass said rear surface of said integral preshaped form liner member, selected ones of said rod-like reinforcing members having end portions of generally hooked configuration, means on said rear surface of said integral preshaped form liner member for receiving and holding captive said hooked end portions of such rod-like reinforcing members to mount said network of reinforcing members on said rear surface of said integral preshaped form liner member in generally spaced relationship therewith, an elongate reinforcing nosing member of substantially L-shaped cross-section mounted on said integral preshaped form liner member adjacent an edge thereof to reinforce such edge of said form liner member against bending forces, and mounting means forming a part of said elongate reinforcing nosing member for attaching thereto ancillary form members of relatively simple geometrical configuration to complete a form assembly of desired overall configuration.