Shear modulus of peat soil at small strain measured by laboratory bender element and cyclic loading test

Shear modulus of peat soil from Akita, Japan is evaluated and discussed in this paper. Bender element and triaxial cyclic loading tests are performed on disturbed and undisturbed specimens. Three techniques for travel time determination on bender element test proposed so far are applied on each specimen to discuss the resulting error on shear modulus evaluation. Estimated G - σ relationships show that the difference of shear modulus between cyclic loading and bender element tests is practically negligible and that the value of shear modulus is approximately 25% less than those from overseas or domestic reports. It is also described that structural anisotropy of peat soil caused by the fiber orientation has little influence on shear modulus in contrast with on shear strength.