Method of test for building limes Determination of fineness of hydrated lime
1973 Edition

Overview of Scope and Application

• Defines the standardized approach for testing hydrated lime fineness and result documentation.

• Fundamental equation for fineness (Clause 3.2):

  [ \text{Fineness %} = \frac{\text{Mass of hydrated lime passing through sieve}}{\text{Total sample mass}} \times 100 ]

• Results to be expressed as a percentage of total sample mass.

• Rounding to conform with IS 2-1960 standards.

• Reference updated to IS 460 (Part 1)-1978 for related specifications.

• Emphasis on utilizing distilled water complying with revised quality criteria.

flowchart TD
    Sample[Hydrated Lime Sample] --> WeighTotal[Weigh Total Mass]
    WeighTotal --> Sieve[Pass through Designated Sieve]
    Sieve --> WeighPassed[Weigh Material Passing Sieve]
    WeighPassed --> Calculate[Compute Fineness Percentage]
    Calculate --> Report[Document Results as % by Mass]

This section establishes the standardized testing and reporting framework for hydrated lime fineness.

Preparation and Testing of Hydrated Lime Samples

Sample Preparation (Clause 2.1)

• Comply with sampling instructions detailed in Clause 7.2 of IS 712-1973.
• Ensure representative and uncontaminated sample collection.
• Use distilled water meeting updated standards for washing samples.

Fineness Test (Clauses 3.1 & 3.2)

• Arrange IS test sieves from coarser (top) to finer (bottom).
• Place precisely 100 g of hydrated lime onto the uppermost sieve.
• Wash the sample with a moderate water stream, completing within 30 minutes; avoid rubbing residues.
• Dry residues on each sieve at 100 ± 10°C until stable mass is achieved.
• Record the mass of residue retained on each sieve.

Results Expression (Clause 3.2)

• Report the fineness as a percentage of the original sample mass.

flowchart TD
    Start[Prepare Sample per IS 712-1973] --> Place[Place 100g on Top Sieve]
    Place --> Arrange[Stack IS Sieves: Coarse to Fine]
    Arrange --> Wash[Wash with Moderate Water Jet (≤30 min)]
    Wash --> Dry[Dry Residues at 100 ± 10°C]
    Dry --> Weigh[Weigh Residues]
    Weigh --> Calculate[Calculate % Mass Retained]
    Calculate --> Report[Report Values as % of Initial Mass]

Refer to IS 2-1960 and relevant sieve standards for detailed rounding and sieve specifications.

Methodology for Fineness Determination

• Purpose: To measure fineness by quantifying residue left on standard IS sieves.
• Sieve Specification: Employ IS sieves conforming with IS 460-1962.
• Water Quality: Use distilled water in compliance with IS 1070-1960 for washing needs.

Testing Steps:

1. Collect a representative hydrated lime sample.
2. Pass the sample through the designated IS sieve.
3. Weigh the residue retained on the sieve post-sieving.
4. Calculate fineness percentage using:

[ \text{Fineness (%)} = 100 - \left( \frac{\text{Residue Mass}}{\text{Total Sample Mass}} \times 100 \right) ]

Notes:

• Higher fineness corresponds to better lime reactivity and strength.
• Residue above 10% indicates coarser particles, potentially reducing quality.

flowchart LR
    Sample[Hydrated Lime Sample] --> Sieve[Pass through IS Sieve (IS 460)]
    Sieve --> WeighResidue[Weigh Residue]
    Sample --> WeighTotal[Weigh Total Sample]
    WeighResidue & WeighTotal --> Calculate[Compute Fineness Percentage]

This ensures systematic quality evaluation for hydrated lime in construction.

Detailed Procedure for Fineness Assessment

• Stack IS sieves with coarser meshes on top, finer ones beneath.
• Deposit exactly 100 grams of hydrated lime on the top sieve.
• Wash the material through the sieve stack using a gentle water jet within 30 minutes.
• Avoid rubbing residues to prevent particle breakdown.
• Dry residues from each sieve at 100 ± 10°C until mass stabilizes.
• Weigh the dried residue on each sieve.

Reporting of Results

• Indicate the percentage mass of hydrated lime retained on each sieve.
• Round final values as per IS 2-1960 guidelines.

flowchart TD
    PrepareSample[Prepare 100g Sample] --> StackSieves[Stack IS Sieves]
    StackSieves --> Wash[Wash with Moderate Water Jet (≤30 min)]
    Wash --> DryResidue[Dry Residue at 100 ± 10°C]
    DryResidue --> WeighResidue[Weigh Residue on Sieves]
    WeighResidue --> CalculatePercentage[Calculate % Mass Retained]

This procedure guarantees precise fineness measurement essential for quality assurance.

Guidelines for Test Result Reporting

• Final test values must be rounded according to the rounding rules prescribed in IS 2-1960.
• Express fineness outcomes as the percentage by mass of the hydrated lime sample.
• Ensure sample preparation adheres to Clause 7.2 of IS 712-1973.

Formula for Reporting:

[ \text{Fineness (%)} = \left( \frac{\text{Mass of lime passing the sieve}}{\text{Mass of hydrated lime sample}} \right) \times 100 ]

Additional Remarks:

• Utilize distilled water meeting specified quality standards for tests.
• Test sieves should conform to relevant IS specifications.
• This standard is part of a series distinguishing lime testing protocols from IS 712-1964.