ACI case studies
ACI · Put your knowledge to work in context.
ACI Certification is a family of credentials administered by the American Concrete Institute for the people who handle concrete in the field and in the lab - concrete field testing technicians, strength testing technicians, batch plant operators, flatwork finishers, and inspector roles. Rather than a single exam, certification is awarded per program, and each program pairs a written knowledge test with a performance or practical component in most cases. The written exams are multiple choice and lean heavily on procedure: how a test is run, what the tolerances are, what the standard requires, and what to do when field conditions deviate from the specification. Candidates typically come from ready-mix suppliers, testing laboratories, contractors, and public agencies that require certified personnel on the job. The ACI case studies are 5 cases and about 3,123 words.
1Air Content Dispute on a Cold-Weather Deck Pour
A 5,000 psi air-entrained deck mix is being placed at 38 °F ambient with a 60-minute haul. The approved mix design targets 6.0% ± 1.5% air for 3/4 in.
654 words, about 3 min2Plastic Shrinkage Cracking on a Windy Slab
unreinforced exterior slab on grade is placed at 2:00 p.m. on a day with 15 mph wind, 92 °F air temperature, and 25% relative humidity.
638 words, about 3 min3Cylinder Break Results Below fc' on a Column Lift
A 4,000 psi specified compressive strength mix is used for a 12 ft column lift. Six standard 6x12 in.
605 words, about 3 min4Cold-Weather Protection Decision on a Mat Foundation
A 3 ft thick mat foundation is placed in late November. Ambient temperature is 28 °F and falling; the forecast low is 18 °F.
620 words, about 3 min5Slump and Retempering at the Point of Placement
A pump crew is placing a 5,000 psi structural mix with a specified slump range of 4–6 in. Truck 7 arrives at 10:15 a.m.
606 words, about 3 min