ASTM C1790
Full Name
ASTM C1790 – Standard Specification for Fly Ash Facing Brick
Scope
Facing bricks are a component of building exteriors, providing both aesthetic appeal and structural integrity. Incorporating fly ash into brick manufacturing offers significant environmental and performance benefits. ASTM C1790 ensures these benefits are consistently achieved by providing manufacturers and specifiers with clear quality standards.
ASTM C1790 specifically addresses the use of fly ash in the production of facing brick. Fly ash, a byproduct of coal combustion, is a valuable resource that can replace a portion of the clay or shale typically used in brickmaking. This substitution reduces reliance on virgin materials and contributes to sustainable construction practices.
The standard outlines specific requirements for fly ash facing brick, including:
- Fly ash content: specifies the minimum percentage of fly ash that must be present in the brick’s composition.
- Compressive strength: establishes minimum compressive strength requirements to ensure the brick’s structural integrity.
- Water absorption: sets limits on water absorption to prevent issues related to freeze-thaw cycles and efflorescence.
- Initial rate of absorption: defines the rate at which the brick absorbs water, impacting its durability and resistance to staining.
- Efflorescence: outlines testing procedures and acceptance criteria for efflorescence, a common aesthetic issue with brickwork.
- Dimensional requirements: specifies tolerances for the brick’s size and shape to ensure proper fit and alignment during construction.
Benefits of using fly ash facing brick:
- Sustainability: utilizing fly ash reduces waste going to landfills and conserves natural resources.
- Durability: fly ash can enhance the brick’s resistance to freeze-thaw cycles, chemicals, and weathering.
- Improved workability: fly ash can improve the plasticity of the clay mixture, making it easier to mold and shape.
- Color consistency: fly ash can contribute to a more uniform color in the finished brick.
- Cost-effectiveness: depending on regional availability, fly ash can be a cost-effective alternative to traditional brickmaking materials.
Resources
Keywords
coal ash; fly ash; compressive strength; water absorption; efflorescence; initial rate of absorption; dimensional stability; flexural strength; drying shrinkage; freeze-thaw resistance; moisture content; saturation coefficient; weathering; durability; aggregate; pozzolanic reaction