Masonry Magazine June 1977 Page. 14
2.
2.1.2 Blended Cements-Specification C 595, for Blended Hydraulic Cements.
2.1.3 Hydrated Lime, Type S-Specification C 207, for Hydrated Lime For Masonry purposes.
2.1.4 Pozzolans-Specification C 618, for Fly Ash and Raw or Calcined Natural Pozzolans for use in Portland Cement Concrete.
2.2 Aggregates shall conform to the following ASTM Specifications, except that grading requirements shall not necessarily apply:
2.2.1 Normal Weight-Specification C 33, for Concrete Aggregates.
2.2.2 Lightweight-Specification C 331, for Lightweight Aggregates for Concrete Masonry Units.
2.3 Other Constituents-Air-entraining agents, coloring pigments, integral water repellents, finely ground silica, etc., shall be previously established as suitable for use in concrete and either shall conform to ASTM Standards where applicable, or shall be shown by test or experience not to be detrimental to the durability of the concrete.
3. Physical Requirements
3.1 Compressive Strength-At the time of delivery to the work site the average compressive strength shall be not less than 8,000 psi, (55MPa) with no individual unit less than 7,200 psi. (50MPa) (Note 4).
3.2 Absorption-The average absorption shall not be greater than 5%, with no individual unit greater than 7%. (Note 4).
Note 4 Strength and absorption properties listed herein are based on satisfactory performance of units used for vehicular traffic in areas subjected to a freeze-thaw environment. In other environments, satisfactory performance may be obtained with units having higher absorption and lower strength.
3.3 Durability-The manufacturer shall satisfy the purchaser either by proven field performance or the laboratory freeze-thaw test that the paving units have adequate durability if they are to be subjected to a freeze-thaw environment.
3.3.1 Proven Field Performance-Satisfactory field performance is indicated when units similar in composition and made with the same manufacturing process as those to be supplied to the purchaser, do not exhibit objectionable deterioration after at least 3 years. The units used as the basis for proven field performance shall have been exposed to the same general type of environment, temperature range and traffic volume as is contemplated for the units supplied to the purchaser.
4.
3.3.2 Freeze-Thaw Test-When tested in accordance with Section 8 of ASTM C 67-73, Specimens shall have no breakage and not greater than 1.0 percent loss in dry weight of any individual unit when subjected to 50 cycles of freezing and thawing. This test shall be conducted not more than 12 months prior to delivery of units.
Permissible Variations in Dimensions
4.1 Length or width of units shall not differ by more than 1/16" (1.6mm) from approved samples. Heights of units shall not differ by more than 1/8" (3.2mm) from the specified standard dimension.
5. Visual Inspection
5.1 All units shall be sound and free of defects that would interfere with the proper placing of the unit or impair the strength or permanence of the construction. Minor cracks incidental to the usual methods of manufacture, or minor chipping resulting from customary methods of handling in shipment and delivery, shall not be deemed grounds for rejection.
6. Sampling and Testing
6.1 The purchaser or his authorized representative shall be accorded proper facilities to inspect and sample the units at the place of manufacture from the lots ready for delivery.
6.2 Sample and test units in accordance with ASTM Methods C 140, Sampling and Testing Concrete Masonry Units, except as required in Section 3.3. For compressive strength and absorption tests, a sample shall consist of 5 specimens.
7. Rejection
7.1 In case the shipment fails to conform to the specified requirements, the manufacture may sort it, and new specimens shall be selected by the purchaser from the retained lot and tested at the expense of the manufacturer. In case the second set of specimens fails to conform to the test requirements, the entire lot shall be rejected.
8. Expense of Tests
8.1 Except as specified in Section 7, and unless otherwise agreed, the expense of inspection and testing shall be borne by the purchaser.