Alternative M_{R} testing techniques for subgrade and subbase soils were developed using a free-free resonant column (FF-RC) test and a static triaxial compression (TX) test considering deformational characreristics of subgrade and sub-base materials....
Alternative M_{R} testing techniques for subgrade and subbase soils were developed using a free-free resonant column (FF-RC) test and a static triaxial compression (TX) test considering deformational characreristics of subgrade and sub-base materials. Synthetic specimens were developed, and the entire testing systems of FF-RC, TX, RC/TS, M_{R} tests were calibrated using synthetic specimens. The alternative M_{R} testing procefures using FF-RC and TX tests were proposed separately, and the predicted M_{R} values on subgrade soils matched well with those determined by standard and sub-base M_{R} test, showing the capability of the proposed methods being used in determining M_{R} values.