The rocking behavior of a shallow foundation of a bridge pier has emerged as an effective mechanism for reducing the seismic load on the superstructure during a strong earthquake. However, a lack of understanding regarding the rocking behavior of shallow foundations has hindered the application of the rocking foundation design philosophy to construction. In this study, the soil-rounding effect on embedded foundations was evaluated to increase understanding of the rocking mechanism. A centrifuge apparatus was used to conduct horizontal slow cyclic tests on an embedded shallow foundation model for three different slenderness ratios (i.e., structure height divided by foundation length) at a centrifugal acceleration of 20 g. The soil-rounding phenomenon was examined according to variations in the soil pressure under the foundation during cyclic loading, and the shape of the rounded soil surface was evaluated as a function of the slenderness ratio. The ultimate moment capacity of the shallow foundation was observed to increase with the side soil pressure; this was verified by comparing the side soil earth pressure with the overturning moment. The rocking mechanism of the embedded shallow foundation was evaluated by focusing on soil rounding.

The performance of nonlinear response history analysis was analyzed based on the historic case of the 2017 Pohang earthquake in Korea. The Yeong-il bay container terminal stopped operations for a period after the Pohang earthquake and intensive site and hazard investigations were conducted. Nonlinear response history analyses using various soil constitutive models, including sophisticated liquefaction models, were performed on the caisson quay wall under two-dimensional plane strain condition. The results of analysis were compared to the hazard investigation results. The analysis results exhibit reasonable agreement with the field measurement data for the earthquake-induced permanent displacement of the quay wall and quay crane rails.