(A) General. Sample and test concrete for slump, air content, temperature, and casting one set of five test cylinders for every 50 cubic yards placed or otherwise directed by client. Concrete temperatures should range from 50° to 85°F.
(B) Laboratory testing requirements.
(1) Test one cylinder (A) at seven days and test two cylinders (B and C) at 28 days. The average of the breaks shall constitute the compressive strength of the concrete sample.
(2) In addition to required information noted previously in this section, record the following information on concrete compression reports:
(a) Test cylinder number and letter;
(b) Specify foundations or structures covered by this test;
(c) Proportions of concrete mix or mix identification;
(d) Specified compressive strength;
(e) Tested compressive strength;
(f) Concrete plastic unit weight;
(g) Name of technician securing sample;
(h) Curing conditions for concrete strength test specimens (field and laboratory);
(i) Date strength specimens transported to laboratory;
(j) Age of strength specimens when tested;
(k) If the initial slump, air content and/or concrete temperature fails, report results to the city prior to placement. It is highly recommended that the contractor wait a few minutes prior to placement to allow the testing to be completed by testing company.
(3) In addition to required information noted previously in this section, record the following information on concrete compression reports:
(a) Elapsed time from batching at plant to discharge from delivery truck at project;
(b) Date and time concrete was placed;
(c) Ambient temperature during concrete placement;
(d) Curing conditions for concrete strength test specimens (preferably a curing box);
(e) Certify the delivery ticket of concrete tested. Report type of concrete delivered, amount of water added and time at which cement and aggregate were loaded into truck and time and duration until concrete is placed on site.
(Ord. 16-2020, passed 12-7-20)