Download or read book Soil structure Interaction Effects on Containment Fragilities and Floor Response Spectra Statistics written by and published by . This book was released on 1987 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil structure Interaction Effects on Containment Fragilities and Floor Response Spectra Statistics written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The probability-based method for the reliability evaluation of nuclear structures developed at Brookhaven National Laboratory (BNL) is extended to include soil-structure interaction effects. A reinforced concrete containment is analyzed in order to investigate the soil-structure interaction effects on: structural fragilities; floor response spectra statistics and acceleration response correlations. To include the effect of soil flexibility on the reliability assessment the following two step approach is used. In the first step, the lumped parameter method for soil-structure interaction analysis is used together with a stick model representation of the structure in order to obtain the motions of the foundation plate. These motions, which include both translations and rotations of the foundation plate, are expressed in terms of the power-spectral density of the free-field ground excitation and the transfer function of the total acceleration response of the foundation. The second step involves a detailed finite element model of the structure subjected to the interaction motions computed from step one. Making use of the structural model and interaction motion the reliability analysis method yields the limit stat probabilities and fragility data for the structure.

Download or read book Soil structure Interaction Effects on the Reliability Evaluation of Reactor Containments written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The probability-based method for the seismic reliability assessment of nuclear structures, which has been developed at Brookhaven National Laboratory (BNL), is extended to include the effects of soil-structure interaction. A reinforced concrete containment building is analyzed in order to examine soil-structure interaction effects on: (1) structural fragilities; (2) floor response spectra statistics; and (3) correlation coefficients for total acceleration responses at specified structural locations.

Download or read book Energy Research Abstracts written by and published by . This book was released on 1988 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1989 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Developments in Dynamic Soil Structure Interaction written by Polat Gülkan and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the last couple of decades it has been recognized that the foundation material on which a structure is constructed may interact dynamically with the structure during its response to dynamic excitation to the extent that the stresses and deflections in the system are modified from the values that would have been developed if it had been on a rigid foundation. This phenomenon is examined in detail in the book. The basic solutions are examined in time and frequency domains and finite element and boundary element solutions compared. Experimental investigations aimed at correlation and verification with theory are described in detail. A wide variety of SSI problems may be formulated and solved approximately using simplified models in lieu of rigorous procedures; the book gives a good overview of these methods. A feature which often lacks in other texts on the subject is the way in which dynamic behavior of soil can be modeled. Two contributors have addressed this problem from the computational and physical characterization viewpoints. The book illustrates practical areas with the analysis of tunnel linings and stiffness and damping of pile groups. Finally, design code provisions and derivation of design input motions complete this thorough overview of SSI in conventional engineering practice. Taken in its entirety the book, authored by fifteen well known experts, gives an in-depth review of soil-structure interaction across a broad spectrum of aspects usually not covered in a single volume. It should be a readily useable reference for the research worker as well as the advance level practitioner. (abstract) This book treats the dynamic soil-structure interaction phenomenon across a broad spectrum of aspects ranging from basic theory, simplified and rigorous solution techniques and their comparisons as well as successes in predicting experimentally recorded measurements. Dynamic soil behavior and practical problems are given thorough coverage. It is intended to serve both as a readily understandable reference work for the researcher and the advanced-level practitioner.

Download or read book INIS Atomindex written by and published by . This book was released on 1996 with total page 794 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1992 with total page 1342 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Structural Dynamics and Soil structure Interaction written by A. S. Cakmak and published by . This book was released on 1989 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil Structure Interaction written by James John Johnson and published by . This book was released on 1981 with total page 874 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil Foundation Structure Interaction written by Rolando P. Orense and published by CRC Press. This book was released on 2010-07-20 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil-Foundation-Structure Interaction contains selected papers presented at the International Workshop on Soil-Foundation-Structure Interaction held in Auckland, New Zealand from 26-27 November 2009. The workshop was the venue for an international exchange of ideas, disseminating information about experiments, numerical models and practical en

Download or read book An Empirical Assessment of Soil structure Interaction Effects on the Seismic Response of Structures written by Jonathan P. Stewart and published by . This book was released on 1996 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Soil Structure Soil Interaction Analysis of Structures in Dense Urban Environments written by Katherine Carys Jones and published by . This book was released on 2013 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: Urban centers are increasingly becoming the locus of enterprise, innovation, and population. This pull toward the center of cities has steadily elevated the importance of these areas. Growth has necessarily spawned new construction. Consequently, modern buildings are often constructed alongside legacy structures, new deep basements are constructed alongside existing shallow foundations, and city blocks composed of a variety of building types result. The underlying soil, foundation, and superstructure of each of these buildings can interact and combine to yield unique seismic responses. Since the seminal work of researchers such as Luco and Contesse (1973) and Wong and Trifunac (1975), researchers have investigated the effects of soil-structure interaction (SSI). This phenomenon refers to the interaction between a single building, its foundation, and the underlying soil during a seismic event. However, as the trend toward urbanization continues, a shortcoming of this conventional SSI approach is that in reality, a structure will almost certainly be located near other structures in metropolitan areas. In this line of research, the interaction of multiple, adjacent buildings during a seismic event, a phenomenon known as structure-soil-structure interaction (SSSI), is investigated. This topic does not yet command the level of attention given to SSI. However, SSSI has the potential to be significantly detrimental or beneficial, depending on the configuration and dynamic properties of the buildings and their foundations in dense urban environments. It is important to understand SSSI effects so that earthquake engineers can make informed decisions about the design and construction of structures in increasingly dense urban areas. As part of a larger, multi-university National Science Foundation (NSF)-supported Network for Earthquake Engineering Simulation Research (NEESR) project, a series of centrifuge experiments were performed at the NEES-supported Center for Geotechnical Modeling (CGM) at the University of California, Davis. Each of these experiments examined aspects of SSI or SSSI through the use of nonlinear structural model buildings situated on different foundations that were supported on deep sand deposits. The centrifuge experiments created a suite of small-scale physical model "case histories" that provided "data" and insight that could be extended through calibrated numerical simulations. The results of the first three centrifuge experiments in the test series (i.e., Test-1, Test-2, and Test-3) were utilized in this dissertation. Numerical analyses are usually only performed for high-profile projects. The effort, expertise and resources required to calibrate and to perform detailed numerical simulations is often prohibitive for typical low- to mid-rise structures. There is a need for a more accessible numerical tool that both geotechnical and structural engineers can utilize to gain insight. In this research, the FLAC finite difference program (Itasca, 2005) with a fully nonlinear effective stress soil constitutive model was used to analyze the centrifuge test-generated "case histories." Test-1 and Test-2 examined SSI and SSSI effects of two moment-resisting frames (MRFs). Test-1 employed a solitary 3-story (prototype) MRF founded on shallow spread footings and a solitary 9-story (prototype) MRF founded on a deep basement (equivalent to 3-stories, prototype) to investigate SSI effects. In Test-2, the 3-story (prototype) and 9-story (prototype) MRFs were placed immediately adjacent to one another to examine SSSI effects. Kinematic interaction effects were primarily observed in these tests. Hence, Test-3 was designed to investigate inertial interaction effects. Three structures were included in Test-3: two MRFs founded on shallow spread footings and one elastic shear-wall structure on a mat foundation. Each of these structures was designed to maximize inertial interaction by: (1) matching the flexible base period of each structure to the soil column to induce resonance, and (2) optimizing structural properties to increase inertial interaction effects. One MRF was positioned alone at one end of the centrifuge model, a SSI condition, and the other MRF and the elastic shear-wall structure were positioned immediately adjacent to each other in the other end of the centrifuge model, a SSSI condition. The rich data set developed through the centrifuge experiments formed the basis of the initial FLAC analyses. A critical aspect of any seismic analysis is the constitutive model used to capture the soil response to cyclic loading. Several soil models were examined during an initial seismic site response analysis. Free-field data from sensors located within the centrifuge soil column were used to quantify the vertical propagation of ground motions through the soil profile. The best model for the dense (Dr = 80%), dry sand used in the centrifuge for Test-1 through Test-3 was a Mohr-Coulomb based model with hysteretic damping, UBCHYST (Naesgaard, 2011). Pseudo-acceleration response spectra and acceleration time histories at the base and at the free-field surface from the centrifuge and the numerical model were compared. The numerical simulations successfully captured the key aspects of the observed seismic site-response for both near-fault pulse-type motions and ordinary motions at a variety of intensities. After successfully capturing the free-field seismic site responses of Test-1 and Test-2, the dynamic responses of the structural models were examined. Each structure was modeled satisfactorily with a two-dimensional, plane-strain numerical model. Engineering design parameters (EDPs) were computed for key structural responses, including (1) transient peak roof drift, (2) residual roof drift, (3) transient peak displacement and (4) peak acceleration at the center of mass of the structure. Additionally, the acceleration time histories and pseudo-acceleration response spectra at the center of mass of the structure for each motion were examined. These metrics were used to compare the numerically estimated dynamic responses with those recorded in the centrifuge experiments. The dynamic response of the 3-story (prototype) MRF estimated with the numerical model was in close agreement with the observed experimental data for both the SSI (Test-1) and SSSI (Test-2) configurations. The more complicated 9-story (prototype) model exhibited greater sensitivity to numerical system inputs, including fixed-base fundamental period and applied structural Rayleigh damping. However, the majority of its recorded dynamic responses were well-matched by the numerical model. The resonant condition created in Test-3 proved challenging to model numerically. The two Test-3 conditions (i.e., SSI and SSSI) were analyzed separately. Significant inertial interaction, including rocking, was observed during the centrifuge test and in the post-processing of data; pseudo-acceleration responses three to five times those recorded in Test-1 and Test-2 were recorded. While the shapes of the pseudo-acceleration response spectra, periods of amplification, and time-histories were well-captured, the numerical model estimated significantly lower amplitudes of the responses for the structures than were observed during the centrifuge test. A sensitivity study was performed to evaluate the influence of several parameters, including (1) the shear wave velocity profile, (2) interface elements, (3) fixed-base fundamental period estimate, and (4) constitutive model parameters. Some of the relative lack of amplification in the numerical simulations was due to over damping in the constitutive model. This was addressed by altering the shear modulus and material damping curves for the soil directly beneath the structures' foundation elements. However, the primary reason for the lower amplitude estimated by the numerical model appeared to be due to the difficulty of capturing the seismic responses of structures in the resonant condition. Shifting the period of any component of the soil-structure system would necessarily have a significant impact on the dynamic response by shifting the system away from resonance. Despite this challenge, the numerical simulations yielded important insights. While the amplitudes of dynamic responses were underestimated for most of the ground motions, the changes in response of the 3-story (prototype) MRF between SSI and SSSI were captured. The elastic shear wall displayed similar behavior; while the spectral shapes were matched for most motions, the amplitudes estimated by the numerical simulations were consistently below those observed in the centrifuge. Comparison of overall change from low- to high-intensity motions or trends from SSI to SSSI could be captured with the model; however, the amplitudes of the responses were generally underestimated. This set of analyses highlighted the challenge of modeling a resonant condition. Additional work is needed to explore the characteristics of the centrifuge when intense input motions are used which are in resonance with the soil in the model. Finally, two prototypical structures were examined. The first, a 3-story MRF, was the model upon which the centrifuge 3-story (prototype) model was based (Ganuza, 2006). Both solitary (SSI) and adjacent (SSSI) configurations were considered for this prototypical 3-story MRF founded on a dense sand soil column. The dynamic responses of the MRF for the solitary (SSI) condition paralleled those observed in the centrifuge experiments. For the considered configurations of adjacent low-rise structures, SSSI effects were found to be either negligible or only slightly beneficial or detrimental for the five ground motions utilized for dynamic analysis. The other prototypical MRF, a 5-story structure, was a simplified version of a typical, medium-rise structure (Ganuza, 2006). The 5-story MRF exhibited dynamic responses consistent with previous work. Amplific.

Download or read book Direct Method for Floor Response Spectra Considering Soil Structure Interaction written by Yang Zhou and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil-Structure Interaction (SSI) analysis is required in structural dynamic analysis under seismic excitations in the current standards, and it significantly influences the Floor Response Spectra (FRS),which are used in the safety assessment for the secondary systems in nuclear power facilities. A direct spectra-to-spectra method is well developed to generate FRS in fixed-basemodels efficiently and accurately. Thus it is necessary to address SSI effect and integrate it into the free field motion as the seismic input for the fixed-base model. For the fully or partly embedded nuclear power reactors, earthquake excitations come from both bottomfoundations and external structures. In this case, the foundations and external structures behave like a foundation systemwith seismic input atmultiple supporting points. The objective of this study is to develop an approach to address SSI effect considering the foundation flexibility and spatially varying ground motions. A substructure method is analytically derived to convert the three dimensional free field motion, i.e., Foundation Input Response Spectra (FIRS) given by site response analysis, into Foundation Level Input Response Spectra (FLIRS). The latter can be used as the seismic input in the direct spectrato- spectra method to generate FRS considering SSI. Only FIRS, dynamic soil stiffness, mass matrix, geometry of the structure, and basic modal information, including natural frequencies and modal shapes, are needed. Both flexible and rigid foundations are considered under the excitation of spatially varying ground motions or uniform seismic input. Furthermore, parametric study is performed to examine the influence of the foundation flexibility on SSI analysis and the resultant FRS. It is observed that FLIRS and FRS are amplified significantly due to SSI effect. This amplification is more severe and the associated frequency is smaller with amore flexible foundation. A semi-analyticalmethod is proposed to generate dynamic soil stiffness of rigid foundations and flexible foundations. Given the soil properties, the Green's influence function is formulated analytically from wave propagation functions. And Boundary ElementMethod (BEM) is employed to determine the dynamic stiffness of foundationswith arbitrary shapes. The resultant 6M×6M dynamic soil stiffness matrix is then used as the generalized soil springs in the proposed substructuremethod. This study presents a fully probabilistic method for addressing the uncertainty resulting from seismic input and soil properties in the generation of FRS.A large number of FLIRS are developed byMonte Carlo simulations,which enables the uncertainty to be propagated from site response analysis to SSI analysis consistently. Then a uniform hazard FLIRS is obtained. Compared to the approach specified in current codes, the uniform hazard FRS lowered the seismic demand significantly to provide amore economical solution for seismic design. Meanwhile, it overcomes the underestimation of FRS by current method in some frequency range. A realistic and continuous distribution is proposed for shear wave velocity (Vs ) to replace the current application. Sensitivity study is performed on the correlation coefficient and the standard derivation of Vs. The results show that these two parameters do not influencemuch in uncertainty analysis. Based on the proposed method, SSI analysis is performed in a realistic model to develop uniform hazard FLIRS for performance-based seismic design, and the direct spectra-tospectramethod is extended to generate safe and economical FRS considering SSI.

Download or read book Dynamic Soil structure Interaction written by Kuen-yaw Shye and published by . This book was released on 1980 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1989 with total page 1672 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soil Structure Interaction in Different Seismic Environments written by and published by . This book was released on 1979 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: