Dr. Villalobos-Jara, Felipe

The dynamic properties of coarse granular soils have been much less studied than in sands. From a database of 14 gravel samples subjected to cyclic triaxial tests, available relationships are studied and new proposed to estimate the normalised shear modulus G/Gmax and the damping ratio D as a function of shear strain γ. The effect of confining stress, fines content, uniformity coefficient and loading frequency on the variation of G/ Gmax and D versus γ is analysed. It is obtained that G/Gmax is dependent on confinement, but not on loading frequency. 85.6% of the data converge in an error band of less than 25% for the proposed formulation. The damping D does depend on fines content as well as confinement and loading frequency. The proposed formulation for D has a 56% probability of having errors less than 25%.