Effective Stress Soil Model Calibration Based on In Situ Measured Soil Properties

Abstract

Numerical analyses for soil structures under monotonic and cyclic loading using nonlinear models have developed rapidly in recent years. Effective stress-based soil models are incorporated in the analyses to predict soil deformation and/or liquefaction. However, in applications to engineering projects, model parameter calibration often becomes an obstacle to the practical use of the model because of the uncertainties and lack of appropriate laboratory test results. This article proposes a procedure to calibrate a soil model for simulating liquefaction and ultimate failure under monotonic and/or cyclic loading, using data based on in situ measurements in the standard penetration test (SPT). The ultimate failure state that limits soil dilation is based on the correlation of residual strength to void ratio, and the state-dependent dilatancy concept. A relationship between soil liquefaction resistance and equivalent number of cycles is developed based on published SPT-based liquefaction triggering charts, together with correlations between a magnitude scaling factor and number of equivalent cycles to liquefaction. Examples to illustrate the application of these concepts are also presented.