AASHTO T2
Full Name
AASHTO T2 – Standard Method of Test for Sampling of Aggregates
Scope
AASHTO T2 is a standardized procedure developed by the American Association of State Highway and Transportation Officials (AASHTO) that provides guidelines for obtaining representative aggregate samples. Aggregates are granular materials such as sand, gravel, or crushed stone used in construction projects. The quality of aggregates significantly influences the performance and longevity of infrastructure, making proper sampling crucial.
The primary purpose of AASHTO T2 is to ensure that the collected samples accurately represent the properties of the bulk aggregate source. This is vital because the characteristics of aggregates, including size distribution, durability, and potential contaminants, directly impact the quality of construction materials like asphalt and concrete.
AASHTO T2 covers various sampling scenarios, including:
- Conveyor belts: obtaining samples from moving conveyor belts using specialized equipment to capture a cross-sectional representation.
- Transport units: sampling aggregates from trucks, railcars, or barges, ensuring samples are taken from different locations within the unit.
- Stockpiles: sampling from stationary aggregate piles, considering pile geometry and potential segregation to obtain representative samples.
- Roadways: extracting cores or sections from existing pavements to assess the condition of the aggregates used in construction.
AASHTO T2 outlines detailed procedures for each sampling scenario, specifying tools, equipment, and techniques. Key aspects include:
- Increment collection: taking multiple increments from different locations within the source to ensure the sample reflects the overall material.
- Sample size: determining the appropriate sample size based on the intended use and the variability of the aggregate source.
- Sample handling and preservation: preventing contamination or alteration of sample properties during transport and storage.
Significance:
Adherence to AASHTO T2 is essential for quality control in construction projects. Representative samples enable accurate testing of aggregate properties, including gradation, durability, and deleterious substances. Test results inform the selection of suitable aggregates for specific applications, ensuring compliance with performance standards and specifications.
AASHTO T2 Accredited Laboratory
Applied Testing & Geosciences, LLC is accredited for performing tests using the AASHTO T2 standard.
Contact us for more information.
Resources
Keywords
aggregates; sampling; increment; stockpile; conveyor belt; transport unit; roadway; bias; contamination; sample preparation; gradation; quality control; representative sample