Canadian Council of Independent Laboratories (CCIL) Practice Exam 2026 – All-in-One Comprehensive Guide to Exam Success!

The required number of strokes per lift for a 250mm cylinder is determined based on the specifications for proper compaction within the guidelines provided by the relevant standards, such as those from the Canadian Council of Independent Laboratories (CCIL). The standard compaction procedure specifies that a 250mm diameter cylinder typically requires around 75 strokes per lift to achieve adequate density and uniformity in the sample being tested.

This number is established to ensure sufficient compaction without overworking the material, which could lead to unrealistic test results. Each stroke contributes to the consolidation of the material, and 75 strokes have been found to balance the need for effective compaction while minimizing the risk of introducing too much air or altering the sample’s characteristics.

Other options such as 60, 70, or 80 strokes would either undershoot or overshoot the target for compacting this specific sample size and could yield results that do not accurately reflect the material properties being tested. Therefore, aligning with the guideline that specifies 75 strokes ensures adherence to the standardized testing protocol and provides reliable data for laboratory testing outcomes.