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Top 10 Items Checked and Verified by QA/QC during Production of Concrete Wall Panels

The quality control process is very important in the production of concrete. Quality checks are done to ensure that concrete panels meet PCI (Precast/Prestress Concrete Institute) standards for high quality aesthetics and structure. During a typical day there will be hundreds/thousands of items verified by the quality department. Listed below are items that I believe have the biggest impact on the quality of a precast/prestressed concrete building. (In no particular order)

• Overall dimensions: length, width, thickness. This is to verify that the panel will fit into the space designated on the building.
• Location of reveals and architectural features. This is to ensure that from one panel to the next the form liner, reveals and thin brick line up around the building.
• Locations and type of steel beam connection embeds, bearing pockets and haunches. Used for load bearing floors and roofs; to confirm that floor and roof elevations are correct.
• Location and type of panel-to-panel steel connections. Typically used to connect adjacent panels together to form a monolithic structure. Checked to verify panels will connect together in the designated locations.
• Location and size of openings for windows and doors. This is to ensure that a window or door will fit into the opening that was cast in the panel.
• Types of finishes and aesthetics. Checked to verify a high quality and uniform finish.
• Types of aggregate, dye, and cement. This is to ensure that the building color is correct and that each panel matches the designated mix design.
• Fresh concrete properties which include: air content, temperature, slump/spread, and density. This is to ensure high quality and durable concrete.
• Cured concrete strength. Every pour has concrete cylinders made to check concrete strength at 1-day cure time and 28-day cure time. This is to ensure high quality and durable concrete.
• Locations and quantity of structural components: prestressing strand, rebar, wythe connectors, lifters. This is to ensure that after a panel is cast it can be safely lifted, shipped to the jobsite and craned onto the building.

Ben Dalsing P.E.
Plant Engineer