Dynamic Responses of Embankment Dams, Constituted from Varied Soil Types, to Seismic Activity

This research delineates a numerical elucidation concerning the flow through an embankment, utilising PLAXIS2D software, and underscores the pivotal influence of soil composition—encompassing gravel, sand, and clay—on the structural resilience of embankments during seismic events. Different material models, incorporating the UBC3D-PLM for sand and the Hardening Soil (HS) small constitutive models for gravel and clay, were strategically employed to replicate embankment behaviours, ensuring a meticulous simulation of distinct soil types. The objective herein was to scrutinise the impact of dynamic loads and soil typologies on pertinent variables: settlements, lateral displacements, and excess pore water pressure engendered within the embankment. A comprehensive series of 2D finite element models, each representative of a specific soil type, were formulated and subsequently subjected to an earthquake record for dynamic analysis. It was discerned that embankments constituted from sand and gravel exhibited a pronounced settlement under dynamic loads, relative to those formulated from clay, primarily attributable to the absence of cohesion forces, augmented porosity, and diminished energy dissipation efficacy. Such factors render sand and gravel more prone to compression and settlement upon exposure to dynamic loads. Moreover, embankments fabricated from sand were identified to generate superior pore pressures compared to their clay or gravel counterparts, a phenomenon attributable to sand’s compressibility which can engender augmented volumetric strains and initiate pumping phenomena, thereby elevating pore pressures. In contrast, gravel and clay materials demonstrated enhanced drainage capabilities and reduced compressibility, facilitating the proficient dissipation of excess pore pressures.