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Engineering properties of rip-rap/rockfill
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Shat sort of analysis are you doing? Dynamic embankment deformation?
You probably won't find much published on Young's mod or Poisson's rat for dumped rockfill. Very hard to measure. Ditto for friction angles, so most values I've seen were just the angle of repose of the dumped fill (which is not necessarily the same as phi', the angle of internal friction), or else large-scale triax tests, which require scalping off everything bigger than 3 or 5 inches so you end up with a different material in your test. You can try Leps, TM, "Review of Shearing Strength of Rockfill" in the ASCE Jnl of the Soil Mechanics and Foundations Division, v 96, no 4, pp 1159-1170, and a paper by Marachi, Chan and Seed in the Jan 1972 issue. (Don't have the title handy.) I don't recall whether they address elastic properties.
Unless your material is shale or something weak like that, you can probably be conservative with a phi' in the high 30s. For the elastic properties of dumped rockfill, you might be able to get close enough by assuming a shear-wave velocity of 900 - 1100 ft/s and Poisson ratio of 0.3, and working from that to Young's mod. My suspicion, however, is that the elastic properties of the rockfill won't matter much in the overall picture.
You probably won't find much published on Young's mod or Poisson's rat for dumped rockfill. Very hard to measure. Ditto for friction angles, so most values I've seen were just the angle of repose of the dumped fill (which is not necessarily the same as phi', the angle of internal friction), or else large-scale triax tests, which require scalping off everything bigger than 3 or 5 inches so you end up with a different material in your test. You can try Leps, TM, "Review of Shearing Strength of Rockfill" in the ASCE Jnl of the Soil Mechanics and Foundations Division, v 96, no 4, pp 1159-1170, and a paper by Marachi, Chan and Seed in the Jan 1972 issue. (Don't have the title handy.) I don't recall whether they address elastic properties.
Unless your material is shale or something weak like that, you can probably be conservative with a phi' in the high 30s. For the elastic properties of dumped rockfill, you might be able to get close enough by assuming a shear-wave velocity of 900 - 1100 ft/s and Poisson ratio of 0.3, and working from that to Young's mod. My suspicion, however, is that the elastic properties of the rockfill won't matter much in the overall picture.
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