Bitumen-based felts - Method of the test, Part 1: Breaking strength test
1993 Edition

IS 13826 Part 1: Scope Overview

• Applicability: This standard specifies test methods and criteria for waterproofing and damp-proofing materials, mainly bitumen-based fabrics.

• Rounding Guidelines: Final results should be rounded following IS 2:1960, maintaining the significant digits as dictated by the standard.

• Breaking Strength Assessment:

  • Average breaking strength is derived from five specimens tested in both warp and weft orientations.
  • Specimens are prepared from the roll as indicated in Figure 1 for warpway and weftway samples.

• Terminology Reference: Definitions are aligned with IS 4911:1980 for bituminous waterproofing terms.

Key Table: Reporting of Breaking Strength (Clause 6.2)

Diagram: Sample Cutting Layout

flowchart LR
    Roll -->|Cut Samples| Warpway[A: Warp direction samples]
    Roll -->|Cut Samples| Weftway[B: Weft direction samples]
    Warpway -->|Test| BreakingStrengthWarp
    Weftway -->|Test| BreakingStrengthWeft

Note: The standard enforces stringent quality control and compliance with BIS inspection and licensing norms for product marking.

IS 13826 Part 1: Definitions Summary

• Terminology Source: Refer to IS 4911:1980 for terminology related to bituminous waterproofing and damp-proofing.
• Rounding Rules: Round final test values according to IS 2:1960, preserving the standard’s specified significant figures.
• Breaking Strength Testing:
  • Average values are computed from five specimens in both warp and weft directions.
  • Specimens are prepared as per Figure 1 layout from the roll.

Formula: Calculating Average Breaking Strength

[ \text{Average Breaking Strength} = \frac{\sum_{i=1}^5 \text{Breaking Strength}_i}{5} ]

• Calculations are performed separately for warp and weft directions.

Notes:

• Definitions are foundational; consult IS 4911 for comprehensive terms.
• Testing and reporting adhere to IS 2 for numerical precision.
• The overseeing committee ensures standard integrity and conformity.

flowchart TD
    A[Roll Sample] --> B[Cut 5 Test Pieces Warp]
    A --> C[Cut 5 Test Pieces Weft]
    B --> D[Compute Average Breaking Strength Warp]
    C --> E[Compute Average Breaking Strength Weft]
    D --> F[Record Results]
    E --> F

This section encapsulates key definitions and testing specifications under IS 13826 Part 1.

IS 13826 Part 1: Breaking Strength Details

• Definition (Clause 3.1): Breaking strength is the tensile force (in Newtons) necessary to fracture the test specimen.

• Measurement (Clause 6.1): Document the breaking force for each specimen in Newtons.

Formula for Breaking Strength

[ \text{Breaking Strength (N)} = \text{Maximum Load at Failure (N)} ]

Important Points:

• Specimens undergo tensile testing until rupture.
• Breaking strength is directly read from the testing apparatus.
• Consistent sample preparation and testing speed as per IS instructions are essential.

Example Table for Recording Breaking Strength

A diagram illustrating the tensile test setup can be provided upon request.

IS 13826 Part 1: Equipment and Apparatus Overview

1. Breaking Strength Test (Clause 6.2):

• The average breaking strength is obtained from five specimens each in warp and weft directions.
• Specimens are cut according to Figure 1 from the roll for warpway and weftway.

2. Rounding Off (General Clause):

• Final results must be rounded following IS 2:1960, preserving the number of significant digits specified.

3. Sample Preparation:

• Samples A and B correspond to warp and weft breaking strength tests respectively.

Summary Table: Reporting Breaking Strength Test

Diagram: Sample Preparation and Testing Flow

flowchart LR
    Roll -->|Cut samples| WarpSamples[5 pieces Warp]
    Roll -->|Cut samples| WeftSamples[5 pieces Weft]
    WarpSamples -->|Test| BreakingStrengthWarp
    WeftSamples -->|Test| BreakingStrengthWeft
    BreakingStrengthWarp -->|Average| FinalWarpValue
    BreakingStrengthWeft -->|Average| FinalWeftValue
    FinalWarpValue --> Report
    FinalWeftValue --> Report

Apparatus must meet precision criteria detailed in IS 13826 clauses and IS 2:1960 for rounding.

IS 13826 Part 1: Specimen Preparation Guidelines

• Specimen Dimensions: Cut five specimens each measuring 75 mm width and 180 mm length (between grips).
• Cutting Directions: Prepare samples in both longitudinal and transverse orientations as depicted in Figure 1.
• Cutting Instruments: Utilize appropriate cutting tools in line with Clause 4.2 to ensure clean and precise edges.
• Result Rounding: Apply rounding rules from IS 2:1960, maintaining the specified significant figures.
• Binder Content: Refer to Part 7 for binder content testing procedures.

Summary Table for Sample Preparation

flowchart LR
    A[Raw Felt Roll] --> B[Cut 5 specimens Longitudinally]
    A --> C[Cut 5 specimens Transversely]
    B & C --> D[Specimens 75 mm x 180 mm]
    D --> E[Testing between grips]

This ensures uniformity and reliability in testing.

IS 13826 Part 1: Testing Procedure Highlights

• Result Rounding: As per IS 2:1960, maintain the same significant figures for final test results.

• Breaking Strength Test: This procedure measures tensile strength by applying load to the specimen until it fails.

• Pressure Head Test (Part 4): Evaluates the material’s resistance to internal pressure without leakage or rupture.

Breaking Strength Calculation

[ \text{Breaking Strength} = \frac{P}{A} ]

Where:

• P = Load at failure (Newtons)
• A = Cross-sectional area (mm²)

Testing Steps

1. Prepare specimen to defined dimensions.
2. Gradually apply tensile force until failure.
3. Record maximum load at failure (P).
4. Calculate breaking strength using the formula.
5. Round off results per IS 2:1960.

flowchart TD
    A[Prepare Specimen] --> B[Apply Tensile Load]
    B --> C{Has Failure Occurred?}
    C -- No --> B
    C -- Yes --> D[Record Load P]
    D --> E[Calculate Breaking Strength]
    E --> F[Round per IS 2:1960]

Refer to IS 13826 Part 1 and IS 2:1960 for detailed instructions.

IS 13826 Part 1: Sample Conditioning Requirements

Conditioning Parameters (Clause 5.1.1)

• Duration: 48 hours
• Temperature: 27 ± 2°C
• Relative Humidity: 65 ± 5%

Sample Preparation (Clause 5.1)

• Cut 5 test specimens
• Dimensions: 75 mm wide × 180 mm long (between grips)
• Cut in both longitudinal and transverse directions

Rounding of Results

• Round final test values in accordance with IS 2:1960, preserving the specified significant figures.

Conditioning Summary Table

flowchart LR
    A[Cut 5 test specimens] --> B[Place in conditioning chamber]
    B --> C[Maintain 27 ± 2°C]
    B --> D[Maintain 65 ± 5% RH]
    C & D --> E[Condition for 48 hours]
    E --> F[Proceed to testing]

Proper conditioning ensures reproducible and accurate testing outcomes.

IS 13826 Part 1: Guidelines for Reporting Results

• Rounding: Final test outcomes are rounded as per IS 2:1960, retaining the standard's specified significant figures.

• Breaking Strength Reporting (Clause 6.2):

  • Report the mean breaking strength of five specimens tested in both warp and weft directions.
  • Strength values are expressed in Newtons (N).
  • Specimens are tested with jaws set at 180 mm gauge length.
  • The force at rupture is recorded from the testing machine’s dial gauge.

• Sample Layout: Specimens for both directions are cut from the roll following the pattern in Figure 1.

Summary Table for Reporting

flowchart LR
    A[Cut 5 specimens] --> B[Test Warp Direction]
    A --> C[Test Weft Direction]
    B --> D[Record Breaking Force (N)]
    C --> E[Record Breaking Force (N)]
    D --> F[Calculate Average Breaking Strength]
    E --> F
    F --> G[Report Rounded Average Values]

This process ensures standardized, consistent reporting of breaking strength for waterproofing felts.

IS 13826 Part 1: Committee Membership Overview

Committee: Water-Proofing and Damp-Proofing Sectional Committee, CED 41

Membership Details:

• Alternates are designated for several members.
• Committee includes representatives from government, industry, and research sectors.

Notes:

• The committee combines expertise across multiple domains to ensure practical, comprehensive standards.
• BIS periodically reviews and updates membership.

graph TD
    A[Chairman: Prof M. S. Shetty] --> B[Committee Members]
    B --> C[Industry Representatives]
    B --> D[Research Bodies]
    B --> E[Government Agencies]
    C --> F[Osnar Chemical Pvt Ltd]
    C --> G[Fosroc India Ltd]
    D --> H[National Test House]