System Response of an Interlayered Deposit with Spatially Preferential Liquefaction Manifestations

The Canterbury Earthquake Sequence produced a spatial pattern of liquefaction-induced surface ejecta at an open field along Palinurus Road in Christchurch, New Zealand, that would not be expected based on simplified liquefaction evaluation procedures. Half the site discharged sand boils and other half did not. Two-dimensional fully-coupled nonlinear dynamic analyses (NDAs) were performed to examine why one-dimensional vulnerability indices (LVIs) overestimated manifestations this for 2010 Darfield 2011 Christchurch earthquakes distinguish between areas with without ejecta. NDAs use PM4Sand PM4Silt constitutive models sand-like clay-like portions subsurface, respectively, within Fast Lagrangian Analysis Continua (FLAC) finite-difference program. Material parameters are obtained from situ geophysical cone penetration test (CPT) data. A sensitivity study is assess influence (1) representative soil property selections CPT inverse filtering procedure correct thin-layer transition zone effects, (2) ground motions developed by two distinct methods (i.e., recordings physics-based simulations), (3) model assumptions affecting diffusion during reconsolidation. Ground deformations flow patterns after shaking examined. results provide insights how stratigraphic details factors can affect system response dictate degree extent manifestations.