TABLE OF CONTENTS Precast concrete panels are often selected for applications requiring high fire resistance and protection against impact and sound Precast panels can be of either loadbearing or curtain wall construction. The former is popular in metal building systems, the latter in parking garages, among other uses. In the past, even precast double-tee roof panels have been used for tall curtain walls. Precast panels can be reinforced with deformed bars and welded wire fabric or can be prestressed. The bars can be epoxy-coated or galvanized to protect against corrosion. To enliven the otherwise gray monotony, architects often specify deep reveals, three-dimensional panel configurations, and exposed-aggregate finishes. For guidance on the design of precast wall panels, the reader is referred to ACI 533R,66 Guide for Precast Concrete Wall Panels, and ACI 31867 by the American Concrete Institute, and to PCI Design Handbook.68
Precast concrete has a low thermal insulation value, and insulated panels consisting of a thick structural part, a thin exterior course, and rigid insulation sandwiched in between have been developed. A 12-in-thick insulated panel might consist of an 8-in structural part, 2.5 in of expanded polystyrene, and 1.5 in of exterior exposed-aggregate concrete. These panels are popular in food processing plants, where strict cleanliness requirements call for hard and smooth interior finishes.
One recurrent issue facing those who investigate distress of precast concrete panels is a lack of design information in the contract documents. It is a rare case in...
