Experimental studies on granular materials demonstrate that the static (large strain) Young's modulus values follow a different trend than the dynamic (small strain) bulk modulus values for pre-consolidated materials. Several researchers have studied the role of confining stress, strain level, and particles stiffness on dynamic and static modulus of granular materials. However, less attention has been made to understand the impact of soil fabric and stress history on both static Young's modulus and dynamic bulk modulus values. In this study, we present results from novel ultrasonic wave propagation experiments conducted on sand (granular quartz) that provide measures of soil elastic properties as a function of applied normal stress. Results are used to further investigate and compare the controlling mechanisms and trends in changes of dynamic bulk modulus and static Young's modulus of the sand layer. The static Young's modulus depends on the stress history and increases significantly for over-consolidated samples, while the dynamic bulk modulus is more related to the existing inter-particle stresses rather than stress history or soil fabric. In contrast to wave velocity, transmitted wave amplitude values were observed to closely follow the stress-strain curve during loading-unloading cycles and the impact of stress history was accurately reflected on the amplitude variations.
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