Soil Dynamic Properties determination: a Neurofuzzy System Approach

Proper characterization of the dynamic behaviour of soil deposits is of utmost importance in earthquake ground-response analyses. Cone-tip penetration resistances, which are usually obtained in a typical geotechnical study for foundation design, can be used to evaluate the dynamic properties and thus to outline dynamically a given soil deposit. Because of the capacity of neurofuzzy techniques to combine the representational aspect of fuzzy models and the learning mechanisms of neural networks, in this paper a neurofuzzy system is proposed to map the values obtained from cone penetration tests into the dynamic properties of Mexico City clays. Utilizing this methodology, it is possible to achieve profies of shear modulus and damping ratios versus shear strain curves, from which soil deposits can be characterized dynamically at a reduced cost.

[1]  Piero P. Bonissone,et al.  Soft computing: the convergence of emerging reasoning technologies , 1997, Soft Comput..

[2]  J. Mendel.  Fuzzy logic systems for engineering: a tutorial , 1995, Proc. IEEE.

[3]  T. Kokusho,et al.  DYNAMIC PROPERTIES OF SOFT CLAY FOR WIDE STRAIN RANGE , 1982 .

[4]  H Harder,et al.  Determination of representative CPT-parameters , 1989 .

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

[6]  Kohji Tokimatsu,et al.  EVALUATION OF LIQUEFACTION RESISTANCE OF CLEAN SANDS BASED ON HIGH-QUALITY UNDISTURBED SAMPLES , 1989 .

[7]  R. Campanella,et al.  Practical aspects of in situ measurements of material damping with the seismic cone penetration test , 1993 .

[8]  Michio Sugeno,et al.  Fuzzy identification of systems and its applications to modeling and control , 1985, IEEE Transactions on Systems, Man, and Cybernetics.

[9]  R. Dobry,et al.  Effect of Soil Plasticity on Cyclic Response , 1991 .

[10]  Didier Dubois,et al.  Possibility Theory - An Approach to Computerized Processing of Uncertainty , 1988 .

[11]  Lotfi A. Zadeh,et al.  Toward a theory of fuzzy information granulation and its centrality in human reasoning and fuzzy logic , 1997, Fuzzy Sets Syst..

[12]  Vilém Novák,et al.  PARADIGM, FORMAL PROPERTIES AND LIMITS OF FUZZY LOGIC , 1996 .

[13]  M. Jefferies,et al.  Use of CPTu to Estimate Equivalent SPT N60 , 1993 .

[14]  John Moody,et al.  Fast Learning in Networks of Locally-Tuned Processing Units , 1989, Neural Computation.

[15]  R. Campanella,et al.  A new approach to measuring dilatancy in saturated sands , 1993 .

[16]  M. P. Romo,et al.  The Mexico Earthquake of September 19, 1985—Correlations between Dynamic and Static Properties of Mexico City Clay , 1988 .