Concrete handling: The separation of coarse aggregate from the mortar matrix during conveying or placement is called

Introduction / Context:
Maintaining uniformity of fresh concrete is crucial for strength and durability. Certain defects occur during transport, placing, or compaction that change the designed proportions locally. This question targets the correct terminology for a common fresh-concrete problem.

Given Data / Assumptions:

• Concrete experiences separation of coarse particles from mortar or paste.
• Occurs due to over-vibration, long drops, or improper mix grading.
• We must select the proper term.

Concept / Approach:
“Segregation” is the tendency for constituents to separate—coarse aggregate rolls ahead or settles while mortar migrates, causing non-uniformity. “Bleeding” is upward water migration forming laitance; “creep” is long-term deformation under sustained load; “shrinkage” is volume reduction from moisture loss or hydration.

Step-by-Step Solution:
Identify the symptom: coarse aggregate separating from mortar → segregation.Eliminate similar but distinct phenomena like bleeding or shrinkage.Choose the correct term.

Verification / Alternative check:
Field guides list causes (improper grading, excess water, high drop heights) and remedies (optimized grading, controlled slump, minimized free fall).

Why Other Options Are Wrong:
Bleeding: water rise, not aggregate separation.Creeping/Shrinkage: hardened concrete behaviors, not fresh placement separation.

Common Pitfalls:
Pouring from excessive height; over-vibration; using very high slump without viscosity modification.

Final Answer:
Segregation.