AASHTO T 383-2023
Evaluation of Asphalt Release Agents (ARAs)
- Standard No.
- AASHTO T 383-2023
- Release Date
- 2023
- Published By
- American Association of State Highway and Transportation Officials US / AASHTO
- Latest
- AASHTO T 383-2018
- Introduction
AASHTO T 383-23 Technical Framework Overview
T 383-23, published by the American Association of State Highway and Transportation Officials (AASHTO) in 2023, provides a systematic approach for the laboratory evaluation of asphalt release agents (ARAs). This standard, under the responsibility of Subcommittee 2b on Liquid Asphalt Technology, governs the performance evaluation of release agents used as coatings on metal surfaces such as truck beds, pavers, rollers, plate lifts, and hand tools.
Scope of Application and Technical Features
This standard focuses on evaluating the functional performance of ARA products in preventing asphalt binder or asphalt mixture from adhering to metal surfaces while ensuring that it does not cause degradation (debonding) of the asphalt mixture. This standard utilizes a dual testing mechanism: an asphalt stripping test to assess the chemical impact of the ARA on the asphalt mixture, and an asphalt desorption test to measure the ARA's anti-sticking effectiveness in practical applications.
Test type Evaluation objective Key parameters Test cycle Asphalt stripping test Effect of ARA on the chemical stability of asphalt mixture Quality change rate, visual rating 168±2 hours Asphalt desorption test Anti-stick performance of ARA on metal surfaces Binder residue percentage, release times Cycle to 10% residue or 7 releases
Asphalt stripping test technical details
The asphalt stripping test utilizes a seven-day immersion method, immersing asphalt mixture samples in both concentrated and diluted ARA for 168 hours. The test requires a mixture with a nominal maximum aggregate size of 12.5 mm that meets the Superpave mix design standard, and an asphalt binder that meets the PG 58-28 or PG 58S-28 performance grade requirements. During the test, six 300 ± 5 g asphalt mixture samples were placed in 600 mL glass beakers. Three samples were immersed in concentrated ARA, three were immersed in ARA diluted to the manufacturer's recommended ratio, and two control groups were included. After immersion, the degree of stripping was assessed by visual comparison and weight change calculation.Peeling Rating System
The standard establishes a four-level visual rating system:
- No Peeling: No discoloration of the ARA and no evidence of peeling in the mix
- Minor Peeling: Minor discoloration of the ARA and peeling of the fine aggregate
- Moderate Peeling: Significant discoloration of the ARA and significant peeling of the fine aggregate
- Severe Peeling: Severe discoloration of the ARA and peeling of both coarse and fine aggregate
Asphalt Desorption Test Implementation Guide
The desorption test simulates actual construction conditions by pouring hot asphalt binder (PG 76-22 or PG 64E-22) onto ARA-treated metal panels. The test uses 11-gauge steel or aluminum panels, ranging in size from 305×305mm to 457×457mm, with a surface texture that simulates the interior of a typical truck bed. The testing process includes: ARA spraying, 5 minutes of rest, 20 ± 2g of hot asphalt pouring, manual peeling after cooling, and weight measurement to calculate the residual rate. This process is repeated until the adhesive residue reaches 10% or seven successful releases are achieved. The test results reflect the ARA product's sustained anti-sticking ability.
Product Formula Reference Parameter Measurement
The standard requires comprehensive physical and chemical property measurements of ARA samples:
Parameter Type Test Standard Technical Significance Application Value Flash Point ASTM D93 Product Safety Assessment Transportation and Storage Safety Guidance ATR-FTIR Spectroscopy ASTM E1252 Chemical Composition Fingerprinting Batch Consistency Verification Solid Content ASTM D2369 Product active ingredient ratio Determination of usage concentration Specific gravity ASTM D1475 Physical property benchmark Quality control parameters pH value ASTM E70 Chemical property characteristics Product stability evaluation
Laboratory implementation technical requirements
The standard imposes strict requirements on laboratory equipment, including: graded glass measuring cylinder, 600mL glass beaker, constant temperature oven with an accuracy of ±0.25°C, 5000g capacity balance (accuracy ±0.02g), etc. Temperature control utilizes thermometers compliant with the M339M/M339 standard, including ASTM E1 mercury thermometers, ASTM E2877 digital metal-stem thermometers, and other types.
Laboratory ambient conditions are defined as 25±4°C (77±7°F). All tests should be conducted under standard laboratory conditions. The reliability of test results depends on the operator's expertise and the calibration and maintenance of the equipment. Laboratories that meet the R18 standard are generally considered to have qualified testing capabilities.
Standard Technical Evolution and Industry Impact
Since its initial publication as a full standard in 2018, the T383-23 standard has undergone significant technical revisions. The 2023 revision strengthens the scientific nature and reproducibility of the test method, particularly by providing detailed provisions for reference parameters for ARA product formulations, providing a technical foundation for product quality control and batch consistency verification.
The implementation of this standard has profound implications for the asphalt pavement construction industry: on the one hand, it standardizes the performance evaluation of release agent products, ensuring the cleanliness and efficiency of construction equipment; on the other hand, it protects the road performance of asphalt mixtures and prevents premature damage caused by improper release agent use.
Implementation Recommendations and Precautions
Based on the requirements of the standard, users are advised to pay attention to the following key points during implementation:
Critical Control Points for Sample Preparation
Asphalt mixture sample preparation must strictly follow T 312 procedures to ensure sample representativeness. Heating temperature should be controlled at 143°C (290°F) for 15-30 minutes. During manual separation, aggregate crushing should be avoided, and fine aggregate particles should be no larger than 6.3mm.
Quality Control During the Test Process
During the peel test, the ARA liquid must completely cover the mixture sample to the 400mL mark, and the sealant film should be used to ensure no evaporation. During the cleaning process, use a No. 200 mesh screen and rinse with room temperature tap water until the ARA is "clean" (the ARA becomes clear or stops foaming).
Safety and Environmental Considerations
The standard clearly indicates that hazardous materials, operations, and equipment may be involved. Users must establish appropriate safety and sanitation practices and determine the applicability of regulatory restrictions. Reference is made to 29 CFR 1910.1200 Hazard Communication Standard and RCRA hazardous waste regulations.
Data Recording and Reporting Requirements
The test report should include complete data for each sample: the degree of peeling and percent mass change for each replicate of the peel test, the percent adhesive residue for each cycle of the desorption test, flash point and test method, infrared spectrum, solids content, specific gravity, pH value, and temperature.
By strictly implementing the T 383-23 standard, industry users can scientifically evaluate the performance of ARA products, ensure the quality of road construction, and promote continuous improvement and innovation in release agent technology.
AASHTO T 383-2023 Referenced Document
- AASHTO M 231 Standard Specification for Weighing Devices Used in the Testing of Materials
- AASHTO M 320 Standard Specification for Performance-Graded Asphalt Binder
- AASHTO M 323 SPECIFICATION FOR SUPERPAVE VOLUMETRIC MIX DESIGN
- AASHTO M 332 Standard Specification for Performance-Graded Asphalt Binder Using Multiple Stress Creep Recovery (MSCR) Test
- AASHTO M 339M/M 339 Thermometers Used in the Testing of Construction Materials
- AASHTO T 312 Preparing and Determining the Density of Asphalt Mixture Specimens by Means of the Superpave Gyratory Compactor.
- AASHTO T 85 Standard Method of Test for Specific Gravity and Absorption of Coarse Aggregate
AASHTO T 383-2023 history
- 2023 AASHTO T 383:2023 Standard Method of Test for Evaluation of Asphalt Release Agents (ARAs)
- 2022 AASHTO T 383:2022 Standard Method of Test for Evaluation of Asphalt Release Agents (ARAs)
- 2021 AASHTO T 383-2021 Standard Method of Test for Evaluation of Asphalt Release Agents (ARAs)
- 2019 AASHTO T 383:2019 Standard Method of Test for Evaluation of Asphalt Release Agents (ARAs)
- 2024 AASHTO T 383-2018 Standard Method of Test for Evaluation of Asphalt Release Agents (ARAs)
