Post-liquefaction settlements occur during and after earthquake shaking. For level ground conditions the amount can be computed from the volumetric re-consolidation strains induced as the excess pore water pressures dissipate. Based on the field experiences during past earthquakes, the amount of volumetric strain depends on penetration resistance and the CSR applied by the design earthquake.


Curves proposed by Ishihara and Yoshimine (1992) are shown in Figure 1 and indicate that volumetric re-consolidation strains can range between about 4.5% for very loose sand to 1% for very dense sand. These curves have been used for estimating post-liquefaction settlements.

 

Figure 1 : Recommended relationships for volumetric re-consolidation strains as a

function of maximum shear strain and relative density (Ishihara & Yoshimi 1992)