a top and bottom the composite structure the composite structure includes a three dimensional structural core constructed of a polymer with a first series of a geometric pattern repeated along its length the structural core also has a second series of the geometric pattern repeated along the width thereof the geometric patter may be a sinusoidal curve or a substantially pyramidal shape the composite structure also includes a first reinforcement layer made of a polymer positioned above the structural core and bonded thereto it also includes a second reinforcement layer made of a polymer that is positioned below the structural core and bonded thereto the composite structure may also include a decorative layer above the first reinforcement layer an acoustical batting layer positioned between the first reinforcement layer and the structural core and may include fire retardant chemicals application_number US 94990410 A description referring now to fig2 a perspective view of one embodiment of the structural core 20 of the present invention is shown the structural core 20 is formed of a pattern of repeating geometries forming peaks 22 and troughs 24 in this illustration the repeating geometries formed are sinusoidal curves the actual measurements and properties of the structural core 20 are.