The Small-Strain Shear Modulus and Damping Ratio of Quartz and Volcanic Sands

The dynamic properties of soils in the region of very small strains are essential for any seismic design. This paper aims to investigate the dynamic small-strain shear modulus (GO) and damping ratio (DO) of reconstituted dry sands of variable mineralogy, shape, and grain-size distribution. In particular, the low-amplitude torsional resonant column test results of 31 specimens are synthesized, 19 specimens of natural and quarry sands predominately composed of quartz particles, and 12 specimens of volcanic sands composed of rhyolitic glassy rock of porous particles. It is concluded that the volcanic sands exhibit significantly lower GO values and slightly lower DO values in comparison to the quartz ones whilst the response of the quartz sands is significantly affected by the shape of the particles. The differences in the observed responses between quartz and volcanic sands are partially attributed to the variability in particles density, morphology, and mineralogy, as well as the higher void ratio and the lower dry density that the volcanic sands exhibit in comparison to the quartz ones. Overall, the effects of the mean effective confining pressure (σm′), the void ratio (e), and the grain-size distribution on the dynamic response of the volcanic soils follow a similar trend as in the quartz sands. Using the general form of available relationships presented in the literature, and after modifying the “constant” parameters, appropriate equations, stemming from the low-amplitude resonant column data test, are proposed that may be used for the estimation of the small-strain shear modulus and damping ratio separately for natural quartz sands, quarry quartz sands, and volcanic granular soils.

[1]  Tuncer B. Edil,et al.  DYNAMIC MODULUS AND DAMPING RELATIONSHIPS FOR SANDS , 1978 .

[2]  Mladen Vucetic,et al.  Cyclic Threshold Shear Strains in Soils , 1994 .

[3]  Rolando P Orense,et al.  Geotechnical Characteristics of Volcanic Soils Taken from Recent Eruptions , 2006 .

[4]  P. Cundall,et al.  A discrete numerical model for granular assemblies , 1979 .

[5]  V. Drnevich,et al.  Evaluation of Dynamic Properties of Sands by Resonant Column Testing , 1984 .

[6]  T. Wichtmann,et al.  Influence of the Grain-Size Distribution Curve of Quartz Sand on the Small Strain Shear Modulus Gmax , 2009 .

[7]  B. Hardin,et al.  Estimating the Shear Modulus of Gravelly Soils , 2005 .

[8]  Yan-Guo Zhou,et al.  Influence of seismic cyclic loading history on small strain shear modulus of saturated sands , 2005 .

[9]  K. Pye,et al.  Particle shape: a review and new methods of characterization and classification , 2007 .

[10]  Fumio Tatsuoka,et al.  EFFECTS OF GRAIN SIZE AND GRADING ON DYNAMIC SHEAR MODULI OF SANDS , 1977 .

[11]  Takeji Kokusho,et al.  CYCLIC TRIAXIAL TEST OF DYNAMIC SOIL PROPERTIES FOR WIDE STRAIN RANGE , 1980 .

[12]  G. Cascante,et al.  Effect of surface roughness on wave propagation parameters , 1998 .

[13]  Kyriazis Pitilakis,et al.  Dynamic Behavior of Sand/Rubber Mixtures, Part II: Effect of Rubber Content on G/G O -γ-DT Curves and Volumetric Threshold Strain , 2012 .

[14]  V. Drnevich,et al.  Shear Modulus and Damping in Soils: Measurement and Parameter Effects (Terzaghi Leture) , 1972 .

[15]  M. Coop,et al.  The influence of particle characteristics on the behaviour of coarse grained soils , 2010 .

[16]  K. Ishihara,et al.  Soil Behaviour In Earthquake Geotechnics , 1996 .

[17]  Kyriazis Pitilakis,et al.  Dynamic properties of dry sand/rubber (SRM) and gravel/rubber (GRM) mixtures in a wide range of shearing strain amplitudes , 2012 .

[18]  T. Youd,et al.  Factors Controlling Maximum and Minimum Densities of Sands , 1973 .

[19]  Farhang Radjai,et al.  BIMODAL CHARACTER OF STRESS TRANSMISSION IN GRANULAR PACKINGS , 1998 .

[20]  V. Drnevich,et al.  SHEAR MODULUS AND DAMPING IN SOILS: DESIGN EQUATIONS AND CURVES , 1972 .

[21]  C. Visone,et al.  Dependency of the Mechanical Behaviour of Granular Soils on Loading Frequency: Experimental Results and Constitutive Modelling , 2007 .

[22]  Fumio Tatsuoka,et al.  SHEAR MODULI OF SANDS UNDER CYCLIC TORSIONAL SHEAR LOADING , 1978 .

[23]  F. E. Richart,et al.  Stress Ratio Effects on Shear Modulus of Dry Sands , 1984 .

[24]  C.R.I. Clayton,et al.  Stiffness at small strain: research and practice , 2011 .

[25]  Surendra K. Saxena,et al.  DYNAMIC MODULI AND DAMPING RATIOS FOR MONTEREY NO. 0 SAND BY RESONANT COLUMN TESTS , 1989 .

[26]  J. Santamarina,et al.  Closure of "Particle Shape Effects on Packing Density, Stiffness, and Strength: Natural and Crushed Sands" , 2006 .

[27]  T. Shibata,et al.  STRESS-STRAIN CHARACTERISTICS OF SANDS UNDER CYCLIC LOADING , 1975 .

[28]  I. Cavarretta,et al.  The influence of particle characteristics on the engineering behaviour of granular materials , 2010 .

[29]  Michele Jamiolkowski,et al.  Design parameters from theory to practice , 1991 .