When pumping concrete shows signs of segregation or blockage, what steps should be taken?

• A. Stop pumping, inspect equipment and lines, verify slump and mix consistency, and correct before resuming; document issue.
• B. Continue pumping and adjust later without inspection.
• C. Increase pump rate to force material through.
• D. Discard the batch entirely.

Answer: (A)

Stop pumping and troubleshoot right away when you see signs of segregation or a blockage. The concrete being pumped should remain uniform; segregation means heavy aggregates are separating from cement paste, which weakens pours and creates inconsistent strengths, while blockages can cause pressure spikes, hose wear, or pump damage. The correct action is to stop, inspect the equipment and all lines for obstructions or wear, and verify the current slump and mix consistency against the project specs. If you find an issue—such as a clogged line, worn hoses, misplaced valves, or a mix that isn’t within the specified slump or viscosity—you correct it before resuming. After addressing the problem, recheck the concrete’s fresh properties and confirm the system is functioning properly, then document the issue and the corrective actions taken so the situation is traceable. Continuing to pump without inspection or trying to push material through a blockage only risks deteriorating the pour and damaging equipment, and changing pump rate won’t fix the underlying problem. Discarding the batch isn’t the default step; it’s reserved for cases where the mix cannot be corrected or has already placed beyond the point of salvage.