Canadian Council of Independent Laboratories (CCIL) Practice Exam 2025 - Free CCIL Practice Questions and Study Guide

During the slump flow test, the objective is to assess the workability and flow characteristics of fresh concrete. It is essential to follow the correct procedure to ensure valid results. The action of rodding the sample is typically not part of this specific test because slump flow focuses on the fluidity and spread of the concrete under its own weight, rather than compacting the sample.

When the cone is initially filled with the fresh concrete, striking off excess material is necessary to create a standardized initial height before the cone is lifted. Raising the cone needs to be done gradually to allow the concrete to flow freely, which aligns with the goal of observing the flow and spread as it settles. Accurate measurement of the spread after the cone is removed is crucial, as it provides the primary data needed to evaluate the concrete's workability. Each of these steps plays a critical role in obtaining accurate and reliable results from the slump flow test, while the action of rodding disrupts the natural behavior of the concrete.