Concrete cohesiveness and stability: increasing the cohesiveness of a fresh concrete mix will make the concrete… (choose the most accurate outcome regarding segregation/bleeding/finishability).

Introduction / Context:
Workability has several facets—consistency, mobility, cohesiveness, and finishability. Among these, cohesiveness reflects the concrete’s resistance to separation of coarse aggregate from mortar. Understanding how cohesiveness influences stability helps field engineers tune mixes to minimize defects such as honeycombing and non-uniform strength.

Given Data / Assumptions:

• We consider conventional fresh concrete without special viscosity-modifying admixtures.
• Segregation means coarse particles separating and settling out of mortar.
• Bleeding is upward water migration; frost scaling is a durability issue after hardening, affected mainly by air entrainment and surface protection.

Concept / Approach:
Higher cohesiveness arises from adequate fines, optimized grading, appropriate paste content, and sometimes admixtures. A cohesive mix keeps aggregate suspended within paste, reducing the likelihood of segregation. Conversely, very low cohesiveness (e.g., very lean or very wet mixes with poor fines) magnifies segregation and bleeding risks.

Step-by-Step Solution:
Define target behavior: we want particles to remain uniformly distributed.Recognize that increased cohesiveness improves “stickiness” of mortar, limiting aggregate slippage and settlement.Therefore, increased cohesiveness makes concrete less liable to segregation.Bleeding and frost scaling depend more on water content, finishing, air entrainment, and curing; cohesiveness alone does not increase those risks.

Verification / Alternative check:
Field checks: well-graded sand and optimized fines reduce segregation at a given slump; SCC concepts demonstrate high cohesion with anti-segregation.

Why Other Options Are Wrong:

• More liable to segregation/bleeding: opposite of how cohesion acts.
• Surface scaling in frost: a hardened-state durability issue, mitigated by air entrainment and curing rather than fresh-state cohesiveness alone.
• None of these: incorrect because a clear outcome exists.

Common Pitfalls:
Chasing high slump by adding water (reducing cohesion); neglecting fines and admixtures needed for pumping or congested reinforcement.

Final Answer:
Less liable to segregation