ASTM C948 is the ASTM standard for measuring dry and wet bulk density, water absorption, and apparent porosity of thin sections of glass-fiber reinforced concrete. It gives users a consistent way to evaluate key physical properties that can affect product performance and quality. For manufacturers, laboratories, and specifiers, this test method supports more reliable comparison of materials and helps document whether thin-section GRC products meet expected technical requirements.

What is ASTM C948?

ASTM C948 is a test method focused on the physical characterization of thin sections of glass-fiber reinforced concrete. Based on its official title, it addresses dry and wet bulk density, water absorption, and apparent porosity, which are common indicators of material structure and condition. The standard is useful when a project or quality program needs measurable data for product evaluation rather than general appearance or nominal properties alone. ASTM C948 provides a defined testing approach for consistent results.

Where is ASTM C948 used?

This standard is commonly used in testing and quality control settings involving thin-section glass-fiber reinforced concrete products. It is relevant anywhere these materials are evaluated for density, absorption, or porosity as part of acceptance, comparison, or product verification. ASTM C948 may be used by material producers, independent testing laboratories, and engineers who need standardized results for procurement or compliance review. It is especially useful when documentation of physical properties is needed in a repeatable, technical format.

Why is ASTM C948 important?

ASTM C948 matters because it helps reduce uncertainty when evaluating thin-section GRC materials. By using a recognized test method for dry and wet bulk density, water absorption, and apparent porosity, users can compare results more consistently across batches, suppliers, or projects. That supports quality control, technical review, and specification compliance. For buyers and producers alike, the standard can improve confidence in reported data and help limit risk when performance-related decisions depend on measured material properties.

• Dry bulk density measurement
• Wet bulk density measurement
• Water absorption evaluation
• Apparent porosity assessment
• Thin-section GRC testing and QC