Modulus of Elasticity for compacted granular backfill

[bbakk]

can anyone tell me a source for accurate modulus of elasticity values for various depths of compacted granular backfill ... 3/4"-0, 1-1/2"-0, 4"-0, a lot of text books show how to calculate stresses and strains but do not give any hints as to the typical material property ...

thanks in advance,

bbakk.

 

[Ron]

The modulus values you require are variable depending upon your compaction state and type of confinement. For the smaller gradation, a cyclic triaxial shear test will give you a value to use. For the larger gradation, it is anyone's guess as to the appropriate modulus value to use as it is greatly dependent upon specific gradation, particle orientation, strength of the parent material, confinement and density.

As for resilient modulus (if you are looking for pavement considerations), then the smaller aggregate would be in the 20 ksi to 60 ksi range, assuming good gradation and compaction.