Macroscale salt-crust formation on indoor playa-like test plots for dust-emission research applications : methodology assessment
Bigl, Matthew F.; LeGrand, Sandra L.; Beal, Samuel A.; Sopher, Ariana M.; Ringelberg, David B.
Playas (dry lakebeds), which are often used as stable surfaces for landing zones and ground maneuver, can also be prolific sources of dust. Accurate prediction of playa susceptibility to dust emission is essential for military operations in arid regions. The goal of this study was to determine if methodologies originally developed for bench-scale laboratory analyses of surficial salt-crust features common to playas could also be used to create macroscale samples for dust-related research applications in a large-scale in-door testing facility. Playa salt crust conditions were simulated on six meter-scale plots (2 m × 2 m) and one large-scale plot (7.3 m × 5.5 m) of compacted, well-mixed loamy soil by controlling climatic parameters, the water-delivery mechanism, and surface-soil heating. The resulting simulated-playa surfaces were characterized for developed crust thickness, compressive and shear strength, chemical composition, and dust-emission potential. Resultant crust attributes varied; however, all methods tested developed simulated playas with physical conditions that were comparable to real-world analogues. Although chemical composition was not evaluated in our real-world comparison, we found that our water delivery method had a statistically significant effect on the chemical attributes of the simulated crusts.
Cold Regions Research and Engineering Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Dust; Dust emission; Dust storms; Engineered environment; Groundwater processes; Playas; Salt Crust; Vehicles, Military
Technical Report (Engineer Research and Development Center (U.S.)) ; no. ERDC/CRREL TR-19-16
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