What type of concrete deck do I have?

Underside Examination – Cast-in-place structural concrete decks will appear monolithic from the underside. Pre-cast structures will be segmental. Composite decks will have a relatively wide spaced I-beam support system. The steel deck is commonly a wide rib type and will exhibit apparent embossment in the corrugations. LWIC placed upon steel decks are generally supported by light framing systems. The most common steel deck types used in conjunction with LWIC are inverted profile form deck, wide rib “B” deck and deep profile “N” deck. Often, the decking will have slots or perforations broken into the bottom of the corrugations for venting. All steel deck used in conjunction with LWIC are galvanized. Topside Examination – A useful tool for the examination of concrete decks is a wood handled masons hammer. Striking a structural material with a modest blow will result in a ringing of the hammer head. Striking non-structural materials result in a dull hollow sound and an impact divot. If determined as being a non-structural material, lightweight concrete and the various types of LWIC can often be visually identified. By way of the visual examination of a deck fragment, the presents of sand aggregate would indicate lightweight concrete. Concrete with a tan coloration having aggregate particles with a brownish silver mica appearance would be a vermiculite or Zonolite LWIC. Concrete containing aggregate particles appearing as white specks would be perlite LWIC. Concrete containing no apparent aggregate and numerous macro air voids would be cellular LWIC. Thanks to Brian Lambert, Garland’s director of products and systems.