Fine Aggregate Quality Tests Flashcards

What is the minimum sample mass required for a sieve analysis (ASTM C136) of fine aggregate?

Answer: 300 g

ASTM C136 requires a minimum sample mass of 300 g for fine aggregate sieve analysis to ensure representative results.

Which ASTM standard governs the mortar-making properties test used to evaluate fine aggregate with elevated organic content?

Answer: ASTM C87

ASTM C87 compares the compressive strength of mortar made with the suspect aggregate to mortar made with washed aggregate to determine if organics are harmful.

The acceptable fineness modulus range for fine aggregate used in concrete typically falls between:

Answer: 2.3 and 3.1

ACI 301 and ASTM C33 specify that the fineness modulus of fine aggregate should be between 2.3 and 3.1 for concrete applications.

When performing the bulk density (unit weight) test per ASTM C29 on fine aggregate using rodding, how many layers are used?

Answer: 3 layers, each rodded 25 times

ASTM C29 rodding procedure uses three equal layers, each consolidated by 25 strokes of the tamping rod.

ASTM C123 is used to determine the percentage of which material in fine aggregate?

Answer: Lightweight pieces

ASTM C123 uses a heavy liquid (such as zinc chloride solution) to float and separate lightweight pieces from the aggregate.

During the ASTM C88 soundness test, how many cycles of immersion and drying are typically performed?

Answer: 5 cycles

The standard soundness test procedure performs 5 cycles of immersion in sulfate solution followed by oven drying.

For ASTM C40 (organic impurities), the sodium hydroxide solution used has a concentration of:

Answer: 3% NaOH by mass

ASTM C40 specifies a 3% sodium hydroxide (NaOH) solution by mass to extract organic compounds from the aggregate for color comparison.