The Effect of the Relative Age of Soil Deposits on Liquefaction-Induced Lateral Spreading

Liquefaction-induced lateral spreading remains a remarkable threat to civil infrastructure in earthquake-prone regions. Despite recent advances, common predictive models of lateral spreading are often associated with large uncertainties. The effects of the depositional setting and age have long been recognized, but not quantified or incorporated into state-of-practice approaches. Specifically, the influence of the relative age of the soil deposits on predicted lateral deformations in riverine environments have not been studied. Thus, this study uses liquefaction-induced lateral spreading observations from the 2010-2011 Canterbury Earthquake Sequence in New Zealand to assess the spatial distribution of the deformations and their relationship with the depositional settings. Observed deformations from active, younger fluvial deposits are compared to those from inactive, older fluvial settings to assess the effect of the relative age of soil deposits and proximity to an active channel. A comparison of the spatial distribution of the observed lateral spreading versus predicted values is presented using the Youd et al. 2002 model. Results from this study suggest that there are quantifiable differences between lateral spreading near active versus abandoned channels, and capturing this difference is important for understanding the influence of depositional environment, sediment age, and for improving predictive models of lateral spreading.