Assessing Cryogenic Testing of Aggregate for Concrete Pavements.
Abstract
Damage to concrete pavements caused by freeze-thaw deterioration of concrete aggregate remains a serious problem. Current tests for determining an aggregate's freeze-thaw durability can take up to 70 days to perform and results from these tests don't always correlate well with field performance. A rapid test for freeze-thaw durability that would accurately predict field service would be a valuable tool for providing durable concrete. Cycling aggregate 10 times between liquid nitrogen and hot water proved useful as a tool to rule out frost-susceptible aggregate. Pore size distribution measurements reveal pore sizes that are critical to freeze-thaw durability. Aggregates with more than 75% of their measurable pore volume between pore diameters of 0.01 and 5 micrometers or with more than 95% of their measurable pore volume smaller than 5 micrometers were susceptible to frost damage. Thus a new freeze-thaw test for aggregates might employ the cryogenic test to screen out all frost- susceptible aggregate and pore size measurement classify the rest. This new test procedure offers results much sooner than current standard test procedures. Further study is needed to refine this method for general use. (MM)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1995
- Accession Number
- ADA293301
Entities
People
- Brian Charest
- Charles Korhonen
Organizations
- Cold Regions Research and Engineering Laboratory