A Unified Formula for Small-Strain Shear Modulus of Sandy Soils Based on Extreme Void Ratios

Abstract

<p>Small-strain shear modulus (G₀) is a fundamental property required in dynamic analyses. For sandy soils, G₀may be affected strongly by particle characteristics such as uniformity coefficient (G_u), mean particle size (d₅₀), fines content (FC), and particle shape. Based on an extensive experimental study of the mechanical behavior of coral sands, this paper proposes a new formula for predicting for sandy soils with various C_u, d₅₀, FC, and particle shapes. A notable feature of the new formula is the use of the extreme void ratios (maximum void ratio e_maxand minimum void ratio e_min) as the indexes, which were shown to be able to account for the effects of the various factors in a simple yet collective manner. Power-law correlations were established between the minimum small-strain shear modulus G_0min and e_maxas well as between the maximum small-strain shear modulus G_0minand e_min. The wide applicability of this formula was validated further using extensive data from the literature from resonant column, bender element, and torsional shear tests on siliceous, calcareous, and coral sandy soils.<br></p>