Accession Number : ADA293301

Title :   Assessing Cryogenic Testing of Aggregate for Concrete Pavements.

Descriptive Note : Special rept.,

Corporate Author : COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH

Personal Author(s) : Korhonen, Charles ; Charest, Brian

PDF Url : ADA293301

Report Date : FEB 1995

Pagination or Media Count : 18

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)

Descriptors :   *CONCRETE, *PAVEMENTS, *AGGREGATES(MATERIALS), PARTICLE SIZE, DAMAGE ASSESSMENT, CEMENTS, FREEZING, FROST, THAWING, COLD WEATHER, CRYOGENICS, CONSTRUCTION MATERIALS, CRUSHING, AIR ENTRAINMENT, SIZE(DIMENSIONS).

Subject Categories : Ceramics, Refractories and Glass
      Civil Engineering
      Construction Equipment, Materials & Supplies

Distribution Statement : APPROVED FOR PUBLIC RELEASE