Effects of Particle Size and Moisture on the High-strain-rate Compressive Behavior of Eglin Sand under Confinement
Huiyang Luo (Dept of Mechanical Engineering, Univ. of Texas at Dallas), William Cooper (Eglin Air Force Base, FL 32542), Hongbing Lu (Univ. of Texas at Dallas)
Dynamic Behavior of Materials
Tue 10:45 - 12:15
Salomon 101
The dynamic compressive behavior of sorted Eglin sand under confinement was characterized under moist conditions at strain rates near 600 s-1 using a modified long split Hopkinson pressure bar. The as-received dry sand was sorted into grain sizes of 0.60 mm, 0.50 mm, 0.42 mm, 0.30 mm, 0.212 mm, 0.15 mm, and 0.106 mm. We used a sand specimen assembly to prepare consistent partially saturated sand specimen. The sand grains were confined inside a steel hollow cylinder and capped by tungsten carbide rods. A given mass of water was added into the dry sand to prepare moist sand specimens with moisture content of 0%, 4.2%, 8.2%, 12.4% and 16.5%. The assembly was subjected to repeat manual shaking and tapping to consolidate the sand to attain a given bulk mass density. It was then sandwiched between incident and transmission bars for compression under high strain rates. The volumetric and deviatoric behavior of sand was investigated on sorted moist sand specimens. The effect of particle size and moisture on the compressive behavior of sand under confinement was discussed. After impact, the sand was dried and sorted for analysis of the particle size distribution. The particles were found to follow the Weibull distribution, and the breakage factor had a linear relationship with moisture level for dense Eglin sand.