Link points to Internet Archive / others. Not hosted by InfraLens. Details
IS 6241:1971 is the Indian Standard (BIS) for method of test for determination of stripping value of road aggregates. This standard specifies the method for determining the stripping value of aggregates used in road construction. The test assesses the adhesion of a standard bituminous binder to pre-coated aggregates after immersion in water, which helps predict the material's resistance to moisture-induced damage.
Method of Test for Determination of Stripping Value of Road Aggregates
! The result is based on visual estimation and can be subjective. It's crucial to have an experienced technician and consistent lighting for repeatable results.
! This standard does not specify the stripping value limit. The acceptable limit (commonly <5%) is typically defined in project-specific documents or codes like MoRTH specifications.
! This is a static test. For a more comprehensive evaluation of moisture susceptibility, dynamic tests like the Rolling Bottle Test or AASHTO T 283 are often performed.
Standard Practice for Effect of Water on Bituminous-Coated Aggregates Using Boiling Water
Assesses stripping of bituminous coating from aggregate by visual inspection after immersion in boiling water.
AASHTO T 182-15 (2023)AASHTO (American Association of State Highway and Transportation Officials), USA
HighCurrent
Standard Method of Test for Coating and Stripping of Bitumen-Aggregate Mixtures
Evaluates stripping by visually estimating the stripped area of coated aggregate after static immersion in water.
EN 12697-11:2020CEN (European Committee for Standardization), Europe
MediumCurrent
Bituminous mixtures - Test methods - Part 11: Determination of the affinity between aggregate and bitumen
Provides multiple methods (e.g., rolling bottle test, static test) to assess affinity, with the principle being similar.
AASHTO T 283-23AASHTO, USA
LowCurrent
Standard Method of Test for Resistance of Compacted Asphalt Mixtures to Moisture-Induced Damage
Addresses the same problem (moisture damage) but uses a quantitative strength-based method on compacted specimens.
Key Differences
≠IS 6241 is a qualitative, subjective test based on visual assessment of loose aggregates, whereas modern standards like AASHTO T 283 provide a quantitative, objective result (Tensile Strength Ratio - TSR) by testing compacted specimens.
≠The conditioning in IS 6241 is a short, aggressive test using boiling water for 10 minutes. In contrast, AASHTO T 182 uses a longer immersion (16-18 hours) at a lower temperature (25°C), and EN 12697-11 (static test) uses a 24-hour immersion, representing different conditioning philosophies.
≠IS 6241 specifies a single aggregate fraction (passing 20 mm, retained on 10 mm). Other standards like EN 12697-11 allow for testing various aggregate size fractions, which may better represent the project's specific gradation.
≠IS 6241 is a simple pass/fail screening tool. AASHTO T 283 and EN 12697-11 are more comprehensive and can also be used to evaluate the effectiveness of anti-stripping additives by comparing results with and without the additive.
Key Similarities
≈The fundamental objective across IS 6241 and its direct equivalents (ASTM D3625, AASHTO T 182) is to simulate the stripping action of water on the bitumen-aggregate bond.
≈The final evaluation in IS 6241, ASTM D3625, and AASHTO T 182 relies on a visual estimation of the percentage of the aggregate surface area that has become uncoated after water immersion.
≈The initial sample preparation process is similar, involving heating aggregate and binder, followed by manual or mechanical mixing to achieve a thorough and uniform coating before conditioning.
Parameter Comparison
Parameter
IS Value
International
Source
Test Method Type
Qualitative visual assessment
Quantitative mechanical test (TSR)
AASHTO T 283
Conditioning Temperature
Boiling water (100°C)
100°C (Boiling)
ASTM D3625
Conditioning Duration
10 minutes
16 to 18 hours
AASHTO T 182
Sample Form
Loose coated aggregate
Compacted cylindrical specimen
AASHTO T 283
Primary Result
Percentage of stripped area (visual)
Tensile Strength Ratio (TSR) in %
AASHTO T 283
Typical Acceptance Limit
Stripping value < 5%
Retained coating > 95%
ASTM D3625
Aggregate Size Fraction
Passing 20 mm, retained on 10 mm
Passing 12.5 mm, retained on 9.5 mm
AASHTO T 182
⚠ Verify details from original standards before use
Key Values5
Quick Reference Values
Test Temperature40 °C
Immersion Duration24 hours
Binder Content for Coating5% by weight of aggregate
Aggregate Size FractionPassing 20 mm IS Sieve and retained on 10 mm IS Sieve
Typical Acceptance Limit (as per MoRTH)<5% stripping
To assess the adhesion between a bituminous binder and an aggregate in the presence of water, indicating the pavement's potential resistance to moisture damage.
What are the standard test conditions?+
Coated aggregates are immersed in a water bath at 40°C for 24 hours (Clause 6.2).
How is the stripping value reported?+
It is reported as the visually estimated percentage of the aggregate surface area that is stripped of the binder (Clause 7).
What aggregate size is used for the test?+
The fraction of aggregate passing the 20 mm IS Sieve and retained on the 10 mm IS Sieve is used (Clause 5.2).