CONCRETE PIPE Plant Prequalification Program The level to which a producer’s quality is scrutinized is what holds the Plant Prequalification Program in the highest regard. Within each respective production facility, all manufacturing processes must be protected from the elements to ensure a controlled environment is maintained. All raw materials, including fine and coarse aggregates, cementing agents, reinforcing steel, admixtures, and gaskets must be stored so as to prevent contamination or degradation. Standard mixes, batching records, moisture controls, marking systems, and curing protocols are also examined in the plant certification program. As far as product performance is concerned, post production tests are conducted on an ongoing basis to ensure design criteria is being attained. Three-edge bearing tests are executed on each size of concrete pipe produced throughout the year as a check against strength, with “first” (hairline) cracks, 0.01 inch cracks, and ultimate failure providing an indication of field performance under worst-case loading conditions. For joint performance, hydrostatic testing is performed as a check for water tightness, with joint openings up to 13 mm evaluated (though some producers also test to 25 mm). Concrete cylinders for both wet and dry cast concrete mixes are taken daily and tested at 1, 7, and 28 day intervals as an additional check for concrete strengths and ensure product specifications are met or exceeded consistently. In addition to the equipment and materials being examined, so too are the personnel responsible for the quality control within each plant. Quality control personnel, at a minimum, must have completed the American Concrete Institute’s Concrete Field Testing Technician Grade 1 program and achieved greater than a 90% mark in the Plant Prequalification Requirements for Precast Concrete Drainage Products exam. The program itself is reviewed regularly, with requirements constantly evolving to ensure today’s best practices become tomorrow’s standards. The concrete pipe industry takes our commitment to quality very seriously. The PPP stamp provides design engineers, contractors, and inspectors assurance that the precast concrete drainage product selected is of the highest quality, and in a world of litigation and liability claims it is a comfort to know that the infrastructure that is being relied upon to perform will continue to do so for decades to come. PAGE 24 LAFARGE PIPE eMANUAL