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.

Evaluation of Liquefaction Potential and Dynamic Properties of Silty Sand Using Cyclic Triaxial Testing

Abstract: The recent earthquake that struck the Bhuj area of Gujarat State in India on 26 January 2001 has caused almost a total devastation of several hundred buildings in villages and cities. Liquefaction triggered by this earthquake caused major damage to structures resting on loose to medium dense sands. This earthquake provides grave illustrations of the importance of understanding the seismic response of such deposits. Recent developments in numerical analyses for nonlinear dynamic responses of ground due to strong earthquake motions have increased the demand for dynamic soil properties corresponding not only at small strain level but also at large strain level. In this paper, the results of cyclic undrained tests are presented for liquefied soil close to the epicenter of the Bhuj earthquake. From these tests the dynamic properties were estimated at large strain levels of 0.5 % to 4 %. The modulus and damping estimated using cyclic triaxial testing at large strain levels might serve as a key factor for assessment of ground response due to eartyquakes.

Nonlinear Lateral, Rocking, and Torsional Vibration of Rigid Foundations

Abstract: Two- and three-dimensional finite element (FE) analyses are performed to investigate the influence of nonlinear soil behavior on the dynamic response of harmonically excited rigid foundations. Lateral, rocking, and torsional vibration modes are considered. An elasto-viscoplastic constitutive model with kinematic hardening is assumed for the foundation soil, and computations are done implicitly in the time domain. The foundation responses for lateral, rocking, and torsional modes are characterized by increased vibrational amplitudes due to material stiffness degradation. Furthermore, resonance frequencies are created that resemble those observed for vertically oscillating finite-size foundations. Nonlinear soil effects are shown to be dominant over a wide range of excitation frequencies for foundations vibrating in torsional and lateral modes. In contrast, nonlinear soil effects are shown to be dominant over a much narrower range of excitation frequencies for the rocking mode. The methodology presented in this paper is useful for nonlinear vibration and transient soil-structure interaction (SSI) analysis.

Effects of liquefiable soil and bridge modelling parameters on the seismic reliability of critical structural components

Abstract: This study investigates the sensitivity of seismic fragility estimates for bridge components to variation in structural and liquefiable soil modelling parameters. A rigorous sensitivity analysis is conducted to evaluate the relative importance of 13 random variables that reflect uncertainty in the seismic performance assessment of bridges in regions with liquefiable soils. The results indicate that the fixed and expansion bearings and bent piles tend to be sensitive to the greatest number of modelling parameters for the case study system, while the abutments are less sensitive. The most significant modelling parameters affecting the seismic fragility include such parameters as undrained shear strength of soil, structural damping ratio, soil shear modulus, gap between deck and abutment, ultimate capacity of soil and fixed and expansion bearing coefficients of friction. The 5% and 95% confidence intervals reveal wide bounds on the seismic fragility curves, particularly for more vulnerable bridge components ...

Modified Topographic Amplification Factors for a Single-Faced Slope due to Kinematic Soil-Structure Interaction

Abstract: In this paper, we evaluate the additive effects of topography, soil nonlinearity, and soil-structure interaction SSI along the crest of an idealized 40 m high cliff-type topographic feature with slope inclination 300, where excessive damage was observed during the Athens 1999 earthquake. The objective of this paper is to investigate the relative contribution of topographic amplification, and kinematic SSI as a function of the incident motion frequency content and geotechnical site conditions for a surface and an embedded structure located at the cliff crest. For this purpose, we perform elastic parametric and nonlinear site-specific two-dimensional finite element simulations using three profiles and six input motions. We illustrate the role of SSI in altering the response at the location of peak topographic amplification potential behind the crest, the effects of incident motion incoherency on the transient structural response, and the beneficial contribution of structural embedment. We finally suggest that empirical models for base-slab averaging of shallow foundations, developed as a function of site conditions, structural dimensions and center line location, could be combined with topographic amplification factors to predict realistic design spectra for structures located on irregular topographic features.

Contact stresses and ground motion generated by soil‐structure interaction

Abstract: A study has been made of the dynamic contact stresses that the foundation of a nine-storey reinforced concrete building exerts on the soil during forced vibration tests. The effects of the flexibility of the foundation on the contact stress distribution and on the force-displacement relationship for the foundation have been examined in an attempt at testing several simplifying assumptions commonly used in soil-structure interaction studies. Comparisons of calculated and observed ground displacements induced by soil-structure interaction in the immediate neighbourhood of the building have also been presented.