A meta-damping model for soil-pile interaction in large-diameter pipe piles under horizontal dynamic loading

Abstract

A comprehensive understanding of soil-pile interaction (SPI) is crucial for applications in earthquake engineering and offshore structures subjected to dynamic loads. The soil plug within large diameter pipe piles plays a significant role in dynamic horizontal loading. Previous models primarily focus on the soil plug’s resistance, neglecting its inertial effects, which leads to discrepancies in predicted natural frequencies and stiffness. This study introduces a meta-damping model to simultaneously account for both the resistance and inertial effects of the soil plug. A theoretical model for pipe piles embedded in saturated soil under horizontal dynamic loading is developed using this model. The model’s validity and accuracy are verified through comparisons with experimental data and existing theoretical models. The impact of the soil plug on the dynamic characteristics of the pile is explored, revealing that traditional plane strain models, which neglect the inertial effects, tend to overestimate the natural frequency and underestimate dynamic damping. The discrepancies are more pronounced for piles with larger diameters and poorer soil properties. This highlights the importance of considering the soil plug’s inertial effects for more accurate dynamic analysis.