PCI Quality Control Technician Level 1 questions with correct answers

You will need early strength from a concrete mixture design in order to strip the product as soon as possible. What type of cement should you consider and what characteristics make it a good choice? CORRECT ANSWER ASTM C150 Type III cement is used when early strength is desired. It is ground finer than the other cements and will react with water faster. Fine and coarse aggregates should generally conform to which standard? CORRECT ANSWER Unless specifically stated otherwise, they should both conform to ASTM C33 How are fine and coarse aggregates defined by the standard and how does a plant check these criteria CORRECT ANSWER Fine and coarse aggregates are generally defined by ASTM C33 in relationship to their gradation or particle size, distribution and fineness for sand. I plant reviews material by testing for and computing the gradation. Non-drinkable water should not be used to make concrete - ture or False? Explain CORRECT ANSWER False - Water suitable for making concrete does not need to be fit for drinking, but non-potable water must meet the chemical limits given in table C3.1.6 of PCI manuals MNL-116 and 117 As a general statement, what are admixtures? CORRECT ANSWER In a general sense, any item added to concrete other than cement, aggregates, and water is an admixture Chorides are detrimental to precast concrete because? CORRECT ANSWER B: Chlorides promote corrosion of embedments, reinforcing, and prestressing strand.