Poisson’s ratio for concrete:
Try it first: pick an option, then read the explanation.
Correct answer: A. Increases with richer mix
Poisson’s Ratio vs Mix Richness
A richer mix has a higher cement content (lower aggregate-to-cement ratio). In richer mixes, the cement paste dominates the mechanical behaviour. Fresh, well-hydrated cement paste has a somewhat higher Poisson’s ratio than the aggregate-paste composite, so a richer mix tends to have a higher Poisson’s ratio. The typical range remains 0.10–0.20 for all normal concretes.
Poisson’s ratio increases with richer mix — option A.
Key takeaway
Richer mix → more paste → slightly higher ν. Values stay in the 0.10–0.20 range regardless of richness.