A Test Method to Measure the Freeze Thaw Durability of Fresh Concrete Using Overpressure

摘要

A recently developed test method is presented that uses a modified version of the ASTM C 231 pressure meter to measure the air void volume and distribution of fresh concrete. The device is called the Super Air Meter, or SAM, and is portable, easy to use, and the test can be completed in 10 minutes. The result is a vast improvement over the 14 days that is typically required for an ASTM C 457 hardened air void analysis to obtain the same data. Validation of the device is presented using over 50 different concrete mixtures with different workability, air void distribution, and combinations of admixtures. For 94% of the data investigated the SAM agreed with the ASTM C 457 hardened air void analysis. The SAM provides a valuable tool for contractors, producers, and owners to determine and evaluate the freeze thaw durability of concrete before it is placed. This is a tool that has the potential to greatly improve the durability and sustainability of concrete pavements.