Evaluation of airfield damage repair methods for extreme cold temperatures

Abstract

To address the need for expedient repair solutions for paved runways in cold environments, airfield damage repair Rapid Airfield Damage Recovery (RADR) materials were tested at temperatures down to-40 ºF. New materials and methods were developed to fill the identified performance gaps for conventional RADR materials. Simulated crater repairs were performed at-20 and-40 ºF. Folded fiber glass panels and hinges met the published tensile strength, but did not meet the required flexural strength. Fiberglass-reinforced polyester panels retained their 73 ºF tensile and flexural strengths down to-40 ºF. If required, foreign object debris covers can be used at temperatures below freezing, but further experimentation is needed to fully assess matting candidates at temperatures below 0 ºF. Geocell sidewalls and junctions showed an increased maximum force, with a tenfold decrease in the displacement before failure. Rapid setting flowable fill and polyurethane foam, prepared conventionally, were demonstrated as backfill materials at temperatures as low as 0 ºF. As a cap material, Rapid Set ® concrete can be placed using conventional techniques down to 17 ºF. Snow and ice materials were demonstrated as backfill materials below freezing and met the strength requirements for capping applications at temperatures down to-40 ºF. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

Ballistic protection using snow

“…thick slush. 1 For a given snow density, we have found that, although taking longer to freeze-up, cellulous-treated snow reaches a notably higher ultimate strength. In several of the gabions, cellulous was scooped from drums and spread over the top of the stockpiled snow.…”

“…Except for the 5.56 mm rounds, penetration after 48 h into celluloustreated snow was greater than for either 24/18-hr or 48-hr gabions without cellulous. This is likely explained by our previous discovery [1] that snow mixed with cellulous sinters more slowly that untreated snow. Immediately after construction, the snow in each gabion was warmer than the surrounding, undisturbed snow, both because of frictional heating during the snowblowing process and the addition of water or water and cellulous.…”

Extreme cold weather airfield damage repair testing at Goose Bay Air Base, Canada

“…When snow in its natural state does not contain enough moisture content to allow good compaction (and subsequent intergranular bond formation), manual wetting can add to the range of application conditions. Laboratory tests (Asenath-Smith et al 2019) show that frozen slush can be an expedient, high-performing crater repair material. Slush, a mixture of natural snow and water, works best for cavity repair in areas where frost enters the ground and persists throughout much of a winter.…”

“…Like frozen slush, cellulose-reinforced slurry (water-snow mixture) should be used when conditions are less than 25°F but greater than −40°F. The advantages to using the cellulose as an additive is that uniaxial compressive tests indicate about a 20% increase in strength over frozen slush by itself (Asenath-Smith et. al 2019).…”

“…Laboratory tests have shown that the strength of a frozen snow-water slurry is significantly greater when a small amount of cellulose is added (Asenath-Smith et al 2019). While it is easier to produce a uniform cellulose-water-snow mixture in the laboratory, we sought to test the impact of this additive in a field setting.…”