Analyzing liquefaction-induced lateral spreads using strength ratios

The writers backanalyzed 39 well-documented liquefaction-induced lateral spreads in terms of a mobilized strength ratio, s_u (mob)σ_vo′ using the Newmark sliding block method. Based on the inverse analyses results, we found that the backcalculated strength ratios mobilized during lateral spreads can be directly correlated to normalized cone penetration test tip resistance and standard penetration test blow count. Remarkably, Newmark analysis-based strength ratios mobilized during these lateral spreads essentially coincide with liquefied strength ratios backcalculated from liquefaction flow failures. The mobilized strength ratios appear to be independent of the magnitude of lateral displacement (at least for displacements greater than 15cm) and the strength of shaking (in terms of peak ground acceleration). Furthermore, the mobilized strength ratios backcalculated from these cases appear to be consistent for a given depositional environment and do not appear to be severely impacted by potential water layer formation.