Unconsolidated, unsaturated material strength
Unconsolidated, unsaturated material strength
(OP)
Looking for suggestions on how to characterize the strength of unconsolidated, dry or moist spoil. The proposal is to construct a cut slope in a previously strip-mined area. The area was reclaimed with cast (loose) spoil. In-place density testing indicates the spoil is between 80-90% MDD. Material is generally classified as GC. Some of the material is moist, but none of it is saturated.
My previous thoughts --
(1) Effective strength from a CU test would not characterize the material as the test consolidates the material before shearing. This does not represent proposed conditions.
(2) I have been told total strength from a UU-test would not apply as the material is not saturated, although the UU could simulate the in-place density.
Anyone run into a similar situation in the past or have any suggestions to test the strength of this material? Thank you for any help you can lend.
My previous thoughts --
(1) Effective strength from a CU test would not characterize the material as the test consolidates the material before shearing. This does not represent proposed conditions.
(2) I have been told total strength from a UU-test would not apply as the material is not saturated, although the UU could simulate the in-place density.
Anyone run into a similar situation in the past or have any suggestions to test the strength of this material? Thank you for any help you can lend.





RE: Unconsolidated, unsaturated material strength
Take a bulk sample, recompact it to the field density and run a direct shear test on it.
METHOD 2:
Guess that the friction angle will be about 33 degrees (or so) and design a slope for 2H:1V.
f-d
¡papá gordo ain’t no madre flaca!