Soil structure interaction

About: Soil structure interaction is a research topic. Over the lifetime, 3653 publications have been published within this topic receiving 48890 citations.

Hydrodynamic and Foundation Flexibility Effects in Earthquake Response of Arch Dams

Abstract: The dynamic responses of Morrow Point Dam to Taft ground motion are presented under various assumptions for the impounded water and foundation rock for a range of properties of the alluvium and sediments at the reservoir boundary. Study of these response results demonstrates that the earthquake response of arch dams is increased by dam‐water interaction and decreased by reservoir boundary absorption, with these effects being more significant in the response of arch dams compared to gravity dams. It is also shown that the magnitudes of these effects depend significantly on the component of ground motion, and that the assumption of a rigid, nonabsorptive reservoir boundary leads to unrealistically large response for dams with impounded water, particularly due to vertical ground motion.

Analysis of Soil Strength Degradation during Episodes of Cyclic Loading, Illustrated by the T-Bar Penetration Test

Abstract: Pipelines and risers form an essential part of the infrastructure associated with offshore oil and gas facilities. During installation and operation, these structures are subjected to repetitive motions which can cause the surrounding seabed soil to be remolded and soften. This disturbance leads to significant changes in the operative shear strength, which must be assessed in design. This paper presents an analytical framework that aims to quantify the degradation in undrained shear strength as a result of gross disturbance—in this case through repeated vertical movement of a cylindrical object embedded in undrained soil. The parameters of the framework were calibrated using data obtained in a geotechnical centrifuge test. In this test a T-bar penetrometer, which is a cylindrical tool used to characterize the strength of soft soil, was cycled vertically in soil with strength characteristics typical of a deep water seabed. Using simple assumptions regarding the spatial distribution of “damage” resulting fr...

The effects of Soil–Structure Interaction on a reinforced concrete viaduct

Abstract: This paper presents a numerical strategy to model a three-pier viaduct made of prestressed concrete. The viaduct was tested pseudodynamically in ELSA laboratory (JRC Ispra, Italy). During the experimental campaign, only the three piers were tested, whereas the behaviour of the deck was simulated using the finite element method. The first part of the paper presents a numerical model of the viaduct based on the Timoshenko multifibre beam elements and non-linear constitutive laws. Comparisons with the experimental results show the good performance of the approach. In the second part, a parametric study is carried out showing the influence of Soil-Structure Interaction (SSI). Various types of soils are considered using a recently developed macro-element representing a rigid shallow foundation. The macro-element is suitable for dynamic (seismic) loadings and it takes into account the plasticity of the soil, the uplift of the foundation, P-theta effects and the radiative damping. Finally, the numerical results are compared with the ones coming from a classical engineering approach using linear elastic springs at the base of the piers. This comparison shows that SSI is a complex phenomenon inducing displacements and internal forces in the structure that are difficult to predict with the linear approach. Based on the results obtained in this paper, it seems now possible to use this approach to investigate numerically the behaviour of a wider variety of configurations.

Centrifuge modelling of sand embankments and islands in earthquakes

Abstract: The bumpy road shaking table system at the Cambridge geotechnical centrifuge was used to conduct an experimental investigation into the effects of earthquakes on sand embankments and islands. The results of the study show that, when a loose or medium dense embankment or island is subjected to an earthquake, positive pore pressures are generated, particularly at the crest. This pore pressure generation softens the embankment and lowers its resonance frequency, resulting in liquefaction and decoupling of surcharge motions from crest motions in the extreme case. When a dense embankment or island is subjected to a strong earthquake, spiky acceleration records are observed at the shoulders of the embankment or island. These records may be attributed to the propagation of dilation fronts through the sand which is in a state of cyclic mobility. If a rigid surcharge is present on the crest, the interaction of the embankment or island with the rigid surcharge gives rise to surcharge accelerations which are charact...