Method of test for abrasion resistance of concrete
1979 Edition

Abrasion Loss Reporting

• Average abrasion loss is determined from 12 test surfaces (4 faces each from 3 cubes).
• Results are reported with a precision of 0.01 grams.
• Expressed as a percentage weight loss.

Suggested Maximum Abrasion Loss Limits

Formula for Abrasion Loss (%):

[ \text{Abrasion Loss} = \frac{\text{Weight Loss (g)}}{\text{Initial Weight (g)}} \times 100 ]

Process Flow Diagram

flowchart LR
    A[Concrete Cubes] --> B[Three Cubes]
    B --> C[Four Faces Each]
    C --> D[Twelve Faces Total]
    D --> E[Abrasion Test Conducted]
    E --> F[Weight Reduction Measured]
    F --> G[Calculate Percentage Loss]
    G --> H[Report Average Abrasion Loss]

This approach guarantees uniform and dependable abrasion loss measurements in line with the standard.

Scope

• The abrasion loss is calculated as the mean percentage loss from 12 faces (4 faces on each of 3 cubes).
• Measurement accuracy is to the nearest 0.01 g.

Maximum Permissible Abrasion Loss (Appendix A-1)

Abrasive Sand Requirements

• Sand must comply with IS 650-1966.
• Particle size to pass through 1.00 mm sieve and be retained on 0.50 mm sieve.
• Sand can be reused after sieving through the 0.50 mm mesh.

Nozzle and Air Pressure

• Air pressure maintained at 0.14 N/mm² (approximately 1.4 bar).
• Nozzle assembly secured with lock nut; hopper cone angle facilitates sand flow.

Abrasion Loss Formula

[ \text{Abrasion Loss} = \frac{\text{Weight Loss}}{\text{Original Weight}} \times 100 ]

Flowchart

flowchart LR
    A[3 Concrete Cubes] --> B[4 Faces Each]
    B --> C[12 Faces Total]
    C --> D[Measure Weight Loss (g)]
    D --> E[Calculate % Abrasion Loss]
    E --> F[Report Average Loss ±0.01 g]

This ensures abrasion resistance is evaluated uniformly according to the standard.

• The method involves abrading the surfaces of concrete cubes using silica sand propelled by compressed air.
• A conical galvanized iron hopper holds the sand and its shape ensures gravity-assisted flow.
• Sand is fed through a nozzle that passes from the hopper bottom through the cabinet top.
• Compressed air pressure is maintained at 0.14 N/mm² (1.4 bar), monitored near the nozzle.
• The abrasive sand conforms to IS 650-1966, sized between 0.5 mm and 1.0 mm.
• Apparatus dimensions are designed to guarantee consistent abrasive flow and impact (refer to the standard's figure).

Key Parameters

Abrasion Test Setup Flow

flowchart TD
    A[Air Compressor] -->|Air @ 0.14 N/mm²| B[Pressure Gauge]
    B --> C[Air Tubing]
    C --> D[Nozzle through Hopper]
    D --> E[Sand in Hopper]
    E --> F[Concrete Cube Surface]

This ensures controlled sand impingement for consistent abrasion resistance testing.

1. Conical Galvanized Iron Hopper

• Holds the abrasive sand, designed with a cone angle to ensure smooth sand flow.
• Nozzle passes through the hopper bottom and cabinet top, secured with lock nut and washer.
• Air pressure gauge installed near the nozzle on copper or brass tubing.
• Operating air pressure is 0.14 N/mm² (1.4 bar).
• Hopper and nozzle dimensions are specified in the standard.

2. Specimen Holder and Cradle

• The cradle moves 17 cm between fixed stops.
• Both cradle and specimen holder are inclined at 10° to the horizontal.
• Nozzle tip is positioned 2.5 cm from the edge of the 10 cm cube specimen.
• Specimen is rotated 180° to provide two abrasion impressions per face.

3. Abrasive Charge

• Sand meeting IS 650-1966 standards.
• Graded to pass 1.00 mm sieve and retained on 0.50 mm sieve.
• Sand can be reused after sieving through the 0.50 mm mesh.

Maximum Abrasion Loss Limits

Apparatus Setup Diagram

flowchart TB
    A[Compressor] -->|0.14 N/mm² Air| B[Pressure Gauge]
    B --> C[Copper/Brass Tubing]
    C --> D[Nozzle Assembly]
    D --> E[Conical Hopper with Sand]
    E --> F[Specimen Holder on Cradle]
    F --> G[Concrete Cube Specimen (10 cm)]

This configuration ensures accurate and reproducible abrasion testing.

Essential Operating Conditions

• Air pressure maintained at 0.14 N/mm² (1.4 bar).
• Abrasive sand charge meets IS 650-1966 standards, sized between 0.5 mm and 1.0 mm.
• Abrasive charge quantity is 4000 grams per impingement.
• Abrasion loss is measured as the mass reduction after two consecutive impressions on the same concrete surface.

Abrasive Sand Details

• Sand must comply with IS 650-1966 grading requirements.
• Particle size distribution ensures consistent abrasion.
• Sand can be recycled after sieving through a 0.50 mm mesh.

Equipment Setup

• Conical galvanized iron hopper with sand inlet holes at the base.
• Nozzle fixed securely through hopper and cabinet top using lock nut and washer.
• Pressure gauge placed near the nozzle to maintain constant air pressure.
• Hopper geometry ensures sand flows freely during testing.

Operating Parameters Summary

Flow Diagram

flowchart TD
    A[Sand Hopper] --> B[Nozzle]
    B --> C[Concrete Specimen Surface]
    D[Compressor] --> E[Air Tube with Pressure Gauge]
    E --> B

This setup guarantees uniform abrasion testing conditions as prescribed.

Preparation Guidelines

• Specimens are 10 cm cubes, cured for 28 days or as delivered.
• Prior to testing, specimens are dried in an oven at 50°C for 24 hours.
• The surface to be tested is abraded lightly with emery paper to reveal aggregate.
• Specimens are mounted on a cradle that moves 17 cm between two fixed points.
• The specimen holder and cradle are inclined at 10° to the horizontal, positioning the test face at 10° to the vertical.
• The nozzle tip is placed 2.5 cm from the specimen edge, centered on half the face.
• Operating conditions include 0.14 N/mm² air pressure and 4000 g sand charge per impingement.
• Each test face receives two abrasion exposures, rotating the specimen 180° between them.
• Abrasion loss is determined by the weight difference before and after testing.

Testing Workflow

flowchart LR
    A[Prepare 10 cm Cube] --> B[Oven Dry at 50°C for 24 hrs]
    B --> C[Surface Rubbed with Emery Paper]
    C --> D[Weigh Specimen]
    D --> E[Mount on Carrier (10° Incline)]
    E --> F[Position Nozzle 2.5 cm from Edge]
    F --> G[Blast with 4000 g Sand at 0.14 N/mm²]
    G --> H[Move Cradle Slowly (17 cm)]
    H --> I[Rotate Specimen 180°]
    I --> J[Repeat Blast]
    J --> K[Clean and Reweigh Specimen]
    K --> L[Calculate Mass Loss]

Abrasion Loss Calculation

[ \text{Abrasion Loss (g)} = W_{before} - W_{after} ]

Where:

• (W_{before}) is the mass before abrasion
• (W_{after}) is the mass after two abrasion cycles

This method standardizes abrasion resistance assessment.

Procedure Steps

• Begin with a weighed, dry concrete cube specimen.
• Place it on the specimen holder so that one smooth vertical face faces the nozzle.
• Position the nozzle tip 2.5 cm from the specimen edge, centered on half the face.
• Impinge the surface with 4000 g of graded sand propelled by compressed air.
• Move the cradle slowly between two set points throughout the test.
• Rotate the specimen 180° horizontally to provide a second abrasion impression on the same face.
• After testing, clean and reweigh the specimen to compute the mass loss.

Additional Information

• The test applies to concrete as well as stone and cement mortar surfaces.
• Results should be rounded according to IS 2-1960 guidelines.
• A lower mass loss indicates superior abrasion resistance.

Test Parameters Summary

Process Flow

flowchart LR
    A[Weighed Dry Specimen] --> B[Place on Holder]
    B --> C[Position Nozzle 2.5 cm from Edge]
    C --> D[Sand Blast with 4000 g Charge]
    D --> E[Move Cradle Slowly]
    E --> F[Rotate Specimen 180°]
    F --> D
    D --> G[Clean and Reweigh Specimen]
    G --> H[Calculate Mass Loss]

This ensures consistent abrasion resistance measurement.

Mass Loss Calculation

[ m = m_1 - m_2 ] Where:

• (m) is the mass loss in grams,
• (m_1) is the specimen mass before abrasion,
• (m_2) is the mass after abrasion (after two impressions on one surface).

Reporting

• The average abrasion loss is calculated over 12 surfaces (4 faces each on 3 cubes).
• Results are rounded to the nearest 0.01 g.
• Reported as a percentage of original mass.

Suggested Maximum Allowable Abrasion Loss

Calculation Flow Diagram

flowchart TD
    A[Initial Specimen Mass (m1)] --> B[Perform Abrasion Test]
    B --> C[Final Mass (m2)]
    C --> D[Calculate Mass Loss (m = m1 - m2)]
    D --> E[Repeat for 12 Test Surfaces]
    E --> F[Compute Average Mass Loss]
    F --> G[Convert to % Loss and Report]

Note

• Follow rounding rules as per the standard.

Abrasion Loss Computation

• Calculate average weight loss over 12 test faces (4 faces on each of 3 cubes).
• Report results to the nearest 0.01 g.
• Express abrasion loss as a percentage of the original weight: [ \text{Abrasion Loss (%) }= \frac{\text{Average Weight Loss}}{\text{Original Weight}} \times 100 ]

Tentative Maximum Abrasion Loss Values

Summary

• Test 12 surfaces (4 faces per cube × 3 cubes).
• Report abrasion loss as a percentage weight reduction.
• Use these limits for evaluating durability of concrete surfaces.

Process Flow

flowchart TD
    A[Test 3 Cubes] --> B[Measure 4 Faces Each]
    B --> C[Calculate Weight Loss per Face]
    C --> D[Average Weight Loss for 12 Faces]
    D --> E[Convert to % Abrasion Loss]
    E --> F[Compare with Maximum Allowable Limits]

This methodology assures consistent abrasion resistance evaluation.

Abrasion Resistance Evaluation

• The method estimates abrasion resistance by measuring mass loss after abrasive sand impingement on concrete cubes (density 24-26 kN/m³).

Key Notes

• Abrasion loss is the mass difference before and after testing.
• Applicable to normal weight concrete, stone, and cement mortar surfaces.
• Simulates wear on surfaces like pavements, industrial floors, platforms, dockyards, and footpaths.

Suggested Permissible Abrasion Losses

Testing Principle

• Abrasive sand impacts the concrete cube surface.
• Measure initial mass (M₁) and final mass (M₂).
• Abrasion loss = M₁ – M₂ (grams).

Additional Information

• Values are provisional and intended for broad guidance.
• Round results per IS 2-1960.
• Helps evaluate concrete mix suitability for abrasion-prone environments.

Flow Diagram

flowchart LR
    A[Prepare Concrete Cube] --> B[Measure Initial Mass (M₁)]
    B --> C[Perform Abrasion Test]
    C --> D[Measure Final Mass (M₂)]
    D --> E[Calculate Abrasion Loss (M₁ - M₂)]
    E --> F[Compare with Recommended Limits]

This facilitates practical assessment of abrasion resistance.