Definition - What does Parabeam Construction mean?
Parabeam construction makes use of a sandwich structured composite material that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. Usually the material in the core in the parabeam construction has low strength but its higher thickness provides the sandwich composite with higher bending stiffness with an overall low density. Thus, this increases the structural strength exponentially while keeping the structure lightweight. It also helps to evenly distribute loads on the structure.
Corrosionpedia explains Parabeam Construction
In parabeam construction, the strength of the sandwich composite material largely depends on two factors:
1. The outer skins.
If the sandwich is supported on both sides, and then stressed by means of a force in the middle of the beam, then the bending moment will introduce shear forces in the material. The shear forces result in the bottom skin being in tension and the top skin being in compression. The core material spaces these two skins apart. A thick core material results in a stronger composite. In principle this works similar to an I-beam.
2. The interface between the core and the skin.
Because the shear stresses in the composite material change rapidly between the core and the skin, the adhesive layer also sees some amount of shear force. If the adhesive bond between the two layers is too weak the most probable result will be delamination.
With parabeam construction, the core and deck layers are woven together, forming an integral sandwich structure that cannot delaminate. When parabeam construction is impregnated with a thermoset resin the material absorbs the resin and the material rises to the preset height due to the capillary forces of the piles in the core. In this one-step process a lightweight and strong sandwich fiberglass panel is formed that offers excellent mechanical properties.