Probabilistic Soil Dynamics: State-of-the-Art

The powerful random vibration techniques can provide probabilistically based descriptions of the response of soils and structures to earthquakes and ocean waves. Although the technology is well developed and uses many of the results of Fourier transform analyses, its general use is retarded by its unfamiliarity and by a substantial tradition behind the description of earthquakes by deterministic methods. Probabilistic analyses of the formal theories of liquefaction have identified many of the uncertainties in those theories and shown that they include quite significant errors. Statistical methods have proven useful in interpreting the historical records of occurrence of liquefaction. The major deficiency as of this writing is in the consistency of the historical data base rather than the analytical tools. Statistical methods have had some use in describing dynamic soil properties.