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Download or read book Site Response, Soil-structure Interaction and Structure-soil-structure Interaction for Performance Assessment of Buildings and Nuclear Structures written by Chandrakanth Bolisetti and published by . This book was released on 2014 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: During an earthquake, the flexibility of the near-surface soil affects the dynamic response of the supported structure. This dynamic interaction is termed soil-structure interaction (SSI). Soil-structure interaction is important for performance-based design, which has seen increasing use in earthquake engineering in the United States in the last decade. Soil-structure interaction analysis is preceded by site-response analysis, which is the process of calculating the response of a soil profile to rock motion at depth. Soil flexibility also results in the interaction of adjacent structures through intermediate soil. This interaction is termed structure-soil-structure interaction (SSSI), which can be important for the performance assessment of buildings, especially those constructed in dense, urban areas. The studies presented in this dissertation share the common goal of a better understanding of the phenomena of site response, SSI and SSSI, and advancing the numerical tools that simulate these phenomena. The state-of-the-art in site-response and SSI analysis of buildings and nuclear structures involves the use of linear or equivalent-linear numerical methods that function in the frequency domain. However, nonlinear time-domain methods may be more appropriate for cases involving intense earthquakes that result in highly nonlinear soil and foundation response. Such nonlinear methods are available but rarely used due to the higher computational requirements and lack of experience with analysts and regulators. This dissertation assesses industry-standard equivalent linear and nonlinear site-response and SSI analysis programs, and provides practical guidelines on their usage. The assessment includes benchmarking the time-domain programs against frequency-domain programs for analyses involving almost linear soil response, and a comparison of the predictions of these programs for analyses involving highly nonlinear soil and foundation response. The assessment also identifies the various pitfalls that can be expected when using these programs and suggests workarounds. Structure-soil-structure interaction has been rarely studied, mainly due to the lack of experimental or field-based case-studies that demonstrate its effects on structural response. The US National Science Foundation funded a research project titled `Seismic Performance Assessment of Buildings in Dense Urban Environments' to understand the significance of SSSI in buildings through a series of centrifuge experiments and numerical simulations. The experiments involve small-scale building models with commonly-found superstructure and foundation configurations. This dissertation describes some of these centrifuge experiments, and their numerical simulations, which are comprehensive and performed using both equivalent-linear and nonlinear SSI analysis programs. The numerical and experimental results show that wave-based SSSI does not significantly affect the global response of the buildings considered in this study.