Composite structure

Abstract

Abstract A corrugated laminate comprises at least two superimposed plies of continuous filament strands bonded together by a hardened plastic resin. The plies are biaxially pre-tensioned prior to hardening of the resin which impregnates and bonds the strands together in a generally concave parabolic configuration at each corrugation. The laminate finds particular application to tubular structures, such as sewer pipe liner and underground tanks, which contribute to the control and improvement in the quality of the nation''s environment. The method and apparatus for making the laminate in the form of a desired composite structure comprises placing a first ply of unidirectional continuous filament strands upon one or more longitudinally spaced pairs of a gapped forming structure so that the ply bridges each forming gap. After the ends of the first ply are held in place, they are pressed and deflected into the forming gaps by a superimposed second ply containing pretensioned, unidirectional continuous filament strands oriented approximately at right angles to the filament strands of the first ply. The parabolic configuration formed at each corrugation of the laminate results from a substantially uniform pressure which is applied to the first ply by the second or deflecting ply. The filament strands of each laminate ply are thoroughly impregnated with the liquid resin which subsequently hardens to bond and maintain the laminate in its corrugated form.

Inventors

• 👤 C Kaempen

Bibliographic Details