Segregation is responsible for ………..

🚫 Effects of Segregation in Concrete

Segregation is the separation of concrete ingredients (coarse aggregate sinking, water/cement paste rising). This causes three distinct defects, all listed in the question:

A — Honeycombing: coarse aggregate clusters without sufficient paste, leaving voids visible on the surface.

B — Porous layers: areas where excess water and fines float up, creating a weak, permeable layer (especially at the top of each lift).

C — Sand streaks: fine material carried along formwork faces by bleed water, leaving pale streaks on the surface.

Key takeaway

Segregation → honeycombing + porous layers + sand streaks. All weaken the concrete and reduce durability. Prevent it with correct w/c, good compaction, and limiting drop height.