Method of test for determination of water transmission rate by capillary action through natural building stones
1967 Edition

Overview of the Standard and Essential Specifications

• Scope: Defines the method to quantify water transmission rate through stones by capillary action, relevant for waterproofing uses.
• Measurement Units: Water loss expressed in grams over a 48-hour period after stabilization (Clause 6.3).
• Balance Accuracy: Requires precision of 0.01 g for weighing (Clause 4.3).
• Test Assembly: Comprises waterproofing compound, distilled water, and a covered glass container (Fig. 1).
• Units: All measurements are in millimeters.
• Reporting: Final results rounded according to IS 2-1960.

Fundamental Equation:

[ \text{Water Transmission Rate} = \frac{\text{Water loss (g)}}{48 \text{ hours}} ]

Referenced Indian Standards (Appendix A):

This standard aligns with global practices to reliably assess waterproofing properties of natural stone adhesives.

Guidance on Sampling Procedures and Criteria

Specifications:

• Sample Selection (Clauses 2.1 - 2.4):

  • Samples should accurately represent the average stone type or grade.
  • If noticeable variations exist, multiple samples must be chosen to cover the full property range.

• Sample Weight and Condition (Clause 2.2):

  • Minimum 25 kg of fresh, unweathered stone per sample.
  • Samples must be taken from distinct strata differing in color, texture, or structure.
  • Exclude any damaged or altered stones (e.g., blasted or heated).

• Field Stones and Boulders (Clause 2.3):

  • Conduct thorough deposit inspections.
  • Document types and conditions of stones.
  • Collect separate samples for each stone class suitable for construction.

Sampling Summary Table

flowchart LR
  A[Inspect Quarry/Deposit] --> B{Is Stone Quality Varied?}
  B -- Yes --> C[Collect Multiple Samples from Different Strata]
  B -- No --> D[Collect Single Representative Sample]
  C & D --> E[Ensure Minimum 25 kg of Fresh Stone]
  E --> F[Exclude Damaged Pieces]
  F --> G[Samples Ready for Testing]

This approach ensures representative material for dependable test outcomes.

Specifications and Dimensions for Test Samples

Specimen Dimensions (Clause 3.1):

• Shape: Square prism
• Cross-sectional area: 5 cm × 5 cm
• Length: 6 cm
• Surface: Square-cut or finely dressed on all faces
• Orientation: 5×5 cm face aligned parallel to stratification planes

Sampling Notes (Clause 2.4):

• Multiple specimens must be taken if significant rock quality variation exists to represent the property range.

Weighing Requirements (Clause 4.3):

• Use a balance with 0.01 g sensitivity for weighing.

Test Setup (Clause 5.1):

• Place specimen centrally in a glass container.
• Fill container with distilled water to approximately three-fourths of depth (1.5 cm).
• Position a cover plate with a central hole over the container.
• Apply wax coating on the specimen portion above the cover to prevent evaporation.

Summary Table of Specimen Dimensions

flowchart TD
  A[Specimen: 5x5 cm Cross-section] --> B[Square Prism]
  B --> C[Length 6 cm]
  C --> D[Placed in Glass Vessel]
  D --> E[Distilled Water at 1.5 cm Depth]
  E --> F[Cover Plate with Central Aperture]
  F --> G[Wax Coating on Exposed Specimen Surfaces]

This ensures uniform specimen preparation and reliable testing.

Details of Apparatus for Measuring Water Transmission

• Glass Vessel:

  • Diameter: 100 mm (10 cm)
  • Depth: 20 mm (2 cm)
  • Material: Shallow glass container with a ground glass flange

• Cover Plate:

  • Central square aperture: 52.5 mm × 52.5 mm
  • Ground glass flange fitting onto vessel flange
  • Flanges greased to ensure airtight and leak-proof connection

• Precision Balance:

  • Sensitivity: 0.01 g

Test Assembly (Refer to Fig. 1)

• Place specimen centrally inside glass vessel.
• Fill vessel with distilled water up to approximately 15 mm (3/4 depth).
• Position cover plate so that specimen protrudes through aperture.
• Apply wax coating on specimen surfaces above cover to prevent evaporation.

Water Transmission Rate Calculation

Water transmission rate (g/48 hours) = Weight loss of water (g) after 48 hours once steady state is reached.

Important Considerations

• Use distilled water exclusively.
• Grease ground glass flanges for a sealed, leak-proof setup.
• Weigh specimens with a precision balance after 48 hours to determine water uptake via capillary action.

flowchart LR
  A[Glass Vessel (10 cm diameter, 2 cm depth)] --> B[Fill with distilled water (1.5 cm depth)]
  B --> C[Place specimen in center]
  C --> D[Cover with plate having 5.25 cm square hole]
  D --> E[Wax coat specimen sides above cover]
  E --> F[Weigh specimen after 48 hours on 0.01 g balance]

This configuration guarantees precise measurement of water transmission per the standard.

Procedure for Measuring Water Transmission Rate through Natural Stones

Key Points:

• Balance Precision: Use a weighing scale accurate to 0.01 g (Clause 4.3).
• Materials: Waterproofing adhesive, distilled water, glass vessel with cover.
• Units: All dimensions in millimeters as per Fig. 1.

Test Steps (Clause 5):

• Record initial specimen weight.
• Perform successive weighings every 24 hours to monitor water loss caused by capillary action (Clause 5.5).
• Apply rounding rules in accordance with IS 2:1960 to final results.

Reporting (Clause 6):

• Document the water transmission rate by capillary action based on specimen weight loss over the test duration.

Rounding Guidelines (IS 2:1960):

flowchart TD
  A[Prepare and Condition Specimen] --> B[Weigh Initial Specimen]
  B --> C[Place in Glass Vessel]
  C --> D[Wait 24 Hours]
  D --> E[Weigh Specimen]
  E --> F[Calculate Weight Loss]
  F --> G[Repeat Weighing Every 24 Hours]
  G --> H[Determine Final Water Transmission Rate]

This ensures an accurate evaluation of water movement through stone samples.

Guidelines for Reporting Results

• Balance Sensitivity: Use a balance with 0.01 g accuracy (Clause 4.3).
• Weighing Schedule: Weigh specimens every 24 hours to track water loss (Clause 5.5).
• Water Loss Rate: Report the rate and duration until water loss stabilizes (Clause 6.2).
• Rounding: Apply IS 2-1960 rounding conventions to the final figures (Clause 6, Note 0.5).

Typical Testing Arrangement (Fig. 1):

• Distilled water in a covered glass vessel.
• Measure water loss through the specimen surface.
• Dimensions specified in millimeters.

Formula for Water Loss Rate

[ \text{Rate} = \frac{\Delta W}{\Delta t} ]

Where:

• (\Delta W): change in weight (grams)
• (\Delta t): time interval (hours)

Reporting Summary Table

flowchart LR
  A[Begin Test] --> B[Fill Vessel with Distilled Water]
  B --> C[Position Specimen]
  C --> D[Initial Weighing (W1)]
  D --> E[Wait 24 Hours]
  E --> F[Subsequent Weighing (W2)]
  F --> G[Calculate Weight Difference \(\Delta W = W_1 - W_2\)]
  G --> H[Calculate Rate \(\Delta W / 24\)]
  H --> I{Is Rate Constant?}
  I -- No --> E
  I -- Yes --> J[Prepare and Submit Report]

This procedure enables consistent and precise documentation of water transmission test results.

Associated Indian Standards Relevant to Natural Building Stones

Key Reference from IS 4121 (Clause 6.3):

• The water transmission rate by capillary action is expressed as the weight of water lost (grams) over 48 hours after stabilization.

Important Notes:

• These standards collectively assist in assessing strength, durability, and moisture behavior of natural stones.
• Perform water absorption tests (IS 1124) prior to capillary water transmission testing (IS 4121).
• Specific gravity and porosity (IS 1122) influence stone durability and moisture movement.

Water Transmission Rate Formula:

[ \text{Water Transmission Rate} = \frac{\text{Water loss (g) after 48 hours}}{\text{Surface area (cm}^2)} ]

This set of Indian Standards provides a thorough framework for evaluating natural stones for construction applications.