ASTM C33 Standard Specification for Concrete Aggregates

ASTM C33 (Standard Specification for Concrete Aggregates) establishes the quality criteria for fine and coarse concrete aggregates. Defines the characteristics of aggregates for good grading, cleanliness, strength, and durability in making concrete. Materials in the fine aggregate that are deleteriously reactive with the alkalis in the cement, in quantities likely to lead to excessive expansion of the mortar or concrete, shall not be present in the aggregate when intended for use in concrete to be exposed to wetting or extended exposure to a humid atmosphere or contact with moist ground. The specification facilitates quality control, selection of materials, and reliability of construction.

Read more

Get Certified ASTM C33 Aggregate Testing for Reliable Concrete Performance

Certification guarantees the quality and grading of aggregates before they are used in concrete production. Certified testing enhances concrete strength, decreases durability issues, and helps meet construction standards.

• Describes the properties of concrete aggregates 
• Determines the quality of grading and cleanliness of aggregates 
• Supports concrete quality control and material selection. For fine and coarse aggregates used in concrete. 
• Helps in the assessment of durability and performance during construction 

Use of ASTM C33

• Identifies aggregate quality for concrete manufacture. 
• Conducts concrete mix design development support.
• Promotes concrete’s durability and strength. 
• Carries out quality assurance and material selection. 
• Decreases construction performance problems. 

Why is aggregate grading important?

Aggregate grading affects the workability, strength, and durability of the concrete mix. Good grading implies optimizing particle packing and minimizing void spaces. Therefore, for engineers, working with ASTM C33 helps them create durable and stable concrete.

Read more

The technician first takes a representative sample of aggregates, following standard sampling procedures. Then the lab conducts a sieve analysis to determine the particle size distribution. The technician also tests impurities, resistance to abrasion, soundness, and cleanliness of the material. Finally, the operator compares the results with ASTM C33 specification limits for acceptance.

Read more

Specimen Size	Concrete aggregate samples (excluding lightweight or heavyweight aggregates are tested per ASTM C33 standard. The specimen size ranges from 12-25 mm (0.5-1.0 in.) square or 12-25 mm in diameter.
Sectioning Machine	A 100 to 150 mm diamond blade and high-accuracy cutting.
Mounting Press	Hot/cold mounting system, normally 25-30 mm in diameter.
Grinding and polishing system	Motorized platen (adjustable speed, 150-600 rpm) and diamond suspensions (600-1M to 100-1M).

ASTM C33 describes the grading of the aggregates in terms of the percentages passing through the standard sieve sizes. The specification also includes the percentage of impurities, abrasion loss, and soundness. Good quality aggregates can improve the strength, workability, and durability of concrete. Excessive impurities or poor grading lead to poor structural performance and service life.

Read more