Prior to lifting the slump mold, concrete must be removed from _____.

• A. The area surrounding the base of the mold
• B. The area around the top surface
• C. The inside of the mold
• D. The outside of the mold

Answer: (A)

The concrete around the base of the mold must be cleared before lifting. This ensures a clean release: if concrete sticks to or surrounds the bottom edge, the mold may cling or drag during lifting, which can bias the measured slump. Clearing the area around the base prevents this interference and gives an accurate, true subsidence value. Removing concrete around the top surface or inside the mold would disturb the sample or isn’t necessary for a proper release, and cleaning the outside of the mold isn’t the critical step for a clean lift.