Effect of fabric anisotropy on dynamic shear modulus in K₀ condition

Dynamic shear modulus is a critical factor for sand in engineering practice. In order to evaluate the effects of fabric anisotropy on dynamic shear modulus, the measurement of wave velocity by bender element technique is conducted. The special container is manufactured to prepare the model with deposition angles of 0°, ± 45° and 90°. The Toyoura sand specimens with specified deposition angles are tested in loading and unloading conditions. The results show that the sand sample prepare in the deposition angle of 90° has the largest shear modulus in horizontal and vertical directions. It is found that in unloading condition, specimens with different deposition angles show different responses for stress history, and response of sand sample with deposition angle of 90° is most obvious, which verify that influence of deposition angle on small strain shear stiffness of sand is very significant. Based on the results, a micromechanical stress-strain model is validated, which could show the influences of fabric anisotropy, stress condition and particle contact characteristics on dynamic shear modulus reasonably.