Typical Void Ratios (fractional) for aggregates – identify the correct combined statement Choose the correct statement regarding approximate void ratios (e) for common aggregate conditions (values are fractional, not percentages).

Introduction / Context:
Void ratio (e) represents the volume of voids divided by the volume of solids. In concrete materials, knowing typical void ratios of aggregates helps assess paste demand, workability, and potential bleeding/segregation tendencies. While exact values vary with grading and packing, some approximate figures are widely used for preliminary estimates.

Given Data / Assumptions:

• Aggregates are in loose to moderately compacted condition as used in batching bins.
• Values are indicative averages; actual site values depend on particle shape and grading.
• Void ratio is expressed as a fraction (for example, 0.45), not a percent.

Concept / Approach:

Single-size coarse aggregates leave larger voids because particles of similar size do not fill interstices effectively, giving e around 0.45 (about 45% voids by volume). Well-graded coarse aggregates pack better, reducing void ratio to roughly 0.40. Clean sands often show e in the 0.40–0.55 range depending on grading and compaction, so 0.45 is a representative order-of-magnitude value for many practical sands.

Step-by-Step Solution:

Verification / Alternative check:

Mix design handbooks tabulate similar void contents/ratios for preliminary paste demand estimates; laboratory measurements by rodded bulk density support these ranges.

Why Other Options Are Wrong:

“None” contradicts common data; selecting any single statement omits the fact that all three are acceptable approximations.

Common Pitfalls:

Confusing “percentage voids” with “void ratio”; ignoring shape effects (angular vs rounded) that can shift these values significantly.

Final Answer:

All of the above