Abstract: A grid structure capable of withstanding a compressive force comprises a peripheral frame, a plurality of first grid members connected to and extending within the peripheral frame and a plurality of second grid members connected to and extending within the peripheral frame. The second grid members intersect the first grid members. The first and second grid members form a grid of small frames disposed within the peripheral frame. The grid has an upper surface and a lower surface wherein a first group of at least a portion of at least one of the first and second grid members have flanges on the upper surface, the flanges being generally perpendicular to the first and second grid members and a second group of at least a portion of at least one of the first and second grid members have flanges on the lower surface, the flanges being generally perpendicular to the first and second grid members. A process of making the grid structure is also disclosed, as is an assembly of such grid structures.