ASTM C939/C939M-22

Overview

ASTM C939/C939M-22 is the Standard Test Method for Flow of Grout for Preplaced-Aggregate Concrete (Flow Cone Method), developed by ASTM International. This standard provides a reliable laboratory and field procedure for assessing the fluidity and flow properties of hydraulic cement grout mixtures. The test method determines the efflux time of a specified volume of grout as it flows through a standardized flow cone, an important indicator of consistency, workability, and suitability for preplaced-aggregate (PA) concrete applications. It is widely used as a quality control tool to ensure grout mixes achieve optimal performance for embedding aggregates and filling voids.

Key Topics

• Scope and Applicability
  • Suitable for both neat grouts and those containing fine aggregates that pass a 2.36 mm (No. 8) sieve.
  • Primarily intended for grouts with an efflux time of 35 seconds or less.
  • The test can be carried out in laboratories or in the field, enhancing its practical value for varied construction environments.
• Test Procedure
  • Involves filling a standardized flow cone with grout, measuring the time required for a specified volume to exit.
  • Ensures the consistency and quality of the grout by regular calibration of apparatus and methodical sampling.
• Reporting
  • Requires detailed documentation, including sample identification, composition, efflux times, temperatures, and mixer type.
• Precision and Limitations
  • Delivers high repeatability within a single laboratory, with tests typically differing by no more than 2.49 seconds.
  • For mixes with higher efflux times, ASTM C109/C109M (flow table method) is recommended for better assessment.
• Safety and Compliance
  • Users must implement safety, health, and environmental controls as required by local regulations and best practices.
  • Internationally recognized principles of standardization are followed, aligned with World Trade Organization TBT principles.

Applications

The ASTM C939/C939M-22 flow cone method has widespread applications in the construction and civil engineering sectors:

• Preplaced-Aggregate Concrete Construction Ensures grout used in embedding aggregates and filling spaces meets the fluidity requirements for full compaction and bonding.
• Quality Control for Grout Mixtures Facilitates consistency across production batches in both onsite and precast operations, helping to reduce defects and improve structural integrity.
• Comparing and Qualifying Materials Supports laboratories and construction managers in verifying the suitability of new or modified grout formulations.
• Field Verification and Continual Monitoring Allows for routine testing during grout placement to ensure ongoing compliance with project specifications.
• Infrastructure and Repair Projects Used in bridge, tunnel, and foundation repairs where effective infiltration and encapsulation of reinforcement or aggregate are critical.

Related Standards

The flow cone method references and interfaces with several other standards to ensure comprehensive testing and consistency in terminology and procedures:

• ASTM C109/C109M - Test Method for Compressive Strength of Hydraulic Cement Mortars Used when grout efflux exceeds 35 seconds.
• ASTM C125 - Terminology Relating to Concrete and Concrete Aggregates Standardizes definitions used within this and related standards.
• ASTM C219 - Terminology Relating to Hydraulic and Other Inorganic Cements Provides further definitions to maintain clarity and uniformity.
• ASTM C938 - Practice for Proportioning Grout Mixtures for Preplaced-Aggregate Concrete Guides the preparation of grout samples for testing.
• ASTM E11 - Specification for Woven Wire Test Sieve Cloth and Test Sieves Governs sieve specifications for aggregate gradation checks.

Keywords: flow cone method, grout fluidity, preplaced-aggregate concrete, ASTM C939/C939M, grout testing, hydraulic cement grout, efflux time, construction quality control, laboratory and field testing.