Download or read book Seismic Response of Base Isolated Buildings Considering Pounding to Moat Walls written by Armin Masroor Shalmani and published by . This book was released on 2013 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seismic isolation offers a simple and direct opportunity to control or even eliminate damage to structures subjected to ground shaking by simultaneously reducing deformations and acceleration demands. A base isolation system decouples the superstructure from the ground resulting in elongation of fundamental period of the structure and reducing the accelerations transferred to superstructure during ground shaking. However, increasing the fundamental period of the structure is mostly accompanied by increased displacement demands. In base isolated structures, this large displacement is concentrated at base level where seismic isolation devices are installed and designed to handle these large deformations without damage. A typical base isolated basement design requires a space in which the building is free to move sideways without hitting the surrounding structure. This space is commonly referred to as the "moat". Structural design codes such as ASCE 7-05 that regulate the design of buildings incorporating seismic base isolation systems require the minimum moat wall clearance distance equal to the maximum displacement at the base of the structure under the Maximum Considered Earthquake (MCE), although the superstructure is designed for design basis earthquake (DBE) level. Despite the cautious regulation for moat wall gap distance, pounding of base isolated buildings to moat walls has been reported in previous earthquakes. In conventional structures, the pounding problem between adjacent structures of buildings and highway bridges has been a major cause of seismic damage, even collapse, during earthquakes in the past several decades. Current design specifications may not adequately account for the large forces generated during impact in base isolated buildings. This study investigates the pounding phenomenon in base isolated buildings from both experimental and analytical perspectives by conducting shake table pounding experiments, developing effective models for impact to moat walls and evaluating the adequacy of code specifications for the gap distance of moat walls. A series of prototype base isolated moment and braced buildings designed by professional engineers for the purpose of this project is presented and one of the models was selected for a quarter scale shake table test with moat walls. The pounding experiments indicate that the contact forces generated during pounding can induce yielding in the superstructure and amplify the response acceleration at all stories of the building. The response amplification and damage depends on the gap distance, moat wall properties, and impact velocity. A detailed finite element model of the test setup is developed in OpenSees. An analytical study on the dynamic behavior of the moat walls resulted in proposing a new impact element. Numerical simulation using the proposed impact element compares well with experimental results. A series of collapse studies using the Methodology in FEMA P695 was conducted for both prototype models at various gap distances. The collapse probability of base isolated models used in this study and the effect of moat wall gap distance on the probability of collapse for base isolated structures is investigated. These studies verify that pounding to moat walls at the required gap distance by ASCE7-05 result in acceptable probability of collapse for the flexible and ductile moment frame models examined. However, the braced frame shows a notable drop in collapse margin ratio because of pounding to moat wall at the required gap distance and requires increasing the gap distance by 17%. to have an acceptable collapse probability.

Download or read book Seismic Response of Base Isolated Buildings Considering Pounding to Moat Walls written by Armin Masroor and published by . This book was released on 2013 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study investigates the pounding phenomenon in base isolated buildings by conducting shake table pounding experiments, developing analytical models for impact to moat walls, and evaluating the adequacy of code specifications for the gap distance of moat walls. The experiments indicated that the contact forces generated during pounding can induce yielding in the superstructure and amplify the response acceleration at all stories of the building. The response amplification and damage depends on the gap distance, moat wall properties, and impact velocity. A detailed finite element model of the test setup was developed in OpenSees and an analytical study on the dynamic behavior of the moat walls resulted in proposing a new impact element. The numerical simulation showed good agreement with the experimental results. Finally, a series of collapse studies using the FEMA P695 methodology was conducted to determine the collapse probability of the base isolated models and the effect of moat wall gap distance on the probability of collapse. These studies verified that pounding to moat walls at the gap distance required by ASCE7-05 results in an acceptable probability of collapse for flexible and ductile moment frame models. However, the braced frame showed a notable drop in collapse margin ratio because of pounding to the moat wall at the required gap distance and requires increasing the gap distance by 17%.to achieve an acceptable collapse probability.

Download or read book International Journal of Computational Methods and Experimental Measurements Volume 3 Issue 1 written by and published by WIT Press. This book was released on 2015-03-31 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Journal of Computational Methods and Experimental Measurements (CMEM) provides the scientific community with a forum to present the interaction between the complementary aspects of computational methods and experimental measurements, and to stress the importance of their harmonious development and integration. The steady progress in the efficiency of computers and software has resulted in the continuous development of computer simulation, which has influenced all scientific and engineering activities. As these simulations expand and improve, the need to validate them grows, and this can only be successfully achieved by performing dedicated experimental tests. Furthermore, because of their continual development, experimental techniques are becoming so complex and sophisticated that they need to be controlled by computers, with the data obtained processed by means of computational methods. The aim of the Journal is to review the latest work in computational methods and experimental measurements, with a view to achieving harmonious development and interaction between the two.

Download or read book Estimating the Seismic Response of Base isolated Buildings Including Torsion Rocking and Axial load Effects written by Keri Lynn Ryan and published by . This book was released on 2005 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Earthquake Induced Structural Pounding written by Robert Jankowski and published by Springer. This book was released on 2015-03-14 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: This books analyzes different approaches to modeling earthquake-induced structural pounding and shows the results of the studies on collisions between buildings and between bridge segments during ground motions. Aspects related to the mitigation of pounding effects as well as the design of structures prone to pounding are also discussed. Earthquake-induced structural pounding between insufficiently separated buildings, and between bridge segments, has been repeatedly observed during ground motions. The reports after earthquakes indicate that it may result in limited local damage in the case of moderate seismic events, or in considerable destruction or even the collapse of colliding structures during severe ground motions. Pounding in buildings is usually caused by the differences in dynamic properties between structures, which make them vibrate out-of-phase under seismic excitation. In contrast, in the case of longer bridge structures, it is more often the seismic wave propagation effect that induces collisions between superstructure segments during earthquakes.

Download or read book Pounding and Impact of Base Isolated Buildings Due to Earthquakes written by Vivek Kumar Agarwal and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As the cost of land in cities increases, the need to build multistory buildings in close proximity to each other also increases. Sometimes, construction materials, other objects and any projections from a building may also decrease the spacing provided between the buildings. This leads to the problem of pounding of these closely placed buildings when responding to earthquake ground motion. The recent advent of base isolation systems and their use as an efficient earthquake force resisting mechanism has led to their increased use in civil engineering structures. At the same time, building codes that reflect best design practice are also evolving. The movement of these base isolated buildings can also result in building pounding. Since base isolation is itself a relatively new technique, pounding phenomenon in base isolated buildings have not been adequately investigated to date. This study looks at the base isolated response of a single two story building and adjacent two story building systems. Four earthquakes with increasing intensity were used in this study. It was found that it is difficult to anticipate the response of the adjacent buildings due to non- linear behavior of pounding and base isolation. The worst case for pounding was found to occur when a fixed base and base isolated buildings were adjacent to each other.

Download or read book Computational Methods in Earthquake Engineering written by Manolis Papadrakakis and published by Springer Science & Business Media. This book was released on 2013-05-30 with total page 643 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an insight on advanced methods and concepts for the design and analysis of structures against earthquake loading. This second volume is a collection of 28 chapters written by leading experts in the field of structural analysis and earthquake engineering. Emphasis is given on current state-of-the-art methods and concepts in computing methods and their application in engineering practice. The book content is suitable for both practicing engineers and academics, covering a wide variety of topics in an effort to assist the timely dissemination of research findings for the mitigation of seismic risk. Due to the devastating socioeconomic consequences of seismic events, the topic is of great scientific interest and is expected to be of valuable help to scientists and engineers. The chapters of this volume are extended versions of selected papers presented at the COMPDYN 2011 conference, held in the island of Corfu, Greece, under the auspices of the European Community on Computational Methods in Applied Sciences (ECCOMAS).

Download or read book Retrofit of Critical Facilities with the Use of Seismic Isolation Including Pounding Phenomena written by Aikaterini Mousteraki and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Seismic isolation is an effective system to protect structural and non-structural components of high-importance structures, such as hospitals, that need to remain functional in the aftermath of earthquakes. Under extreme earthquakes though, the design displacement of the isolation systems might be exceeded; hence impacts against surrounding moat walls and/or adjacent buildings could be generated. During recent earthquakes, pounding phenomena have caused structural damage or even collapse of civil infrastructure.This thesis evaluates the performance of a nine-storey, steel moment resisting frame (MRF) hospital, which is retrofitted by means of seismic isolation. Triple Pendulum Bearings are employed including the potential for poundings. The hospital is a 1960s Type 2 Construction; thus, it has been characterized as the Canadian Seismic Research Network (CSRN) Benchmark Steel MRF Hospital Structure. The base-isolated building is subjected to a set of 40 ground motions that are selected to represent the seismic hazard in a high-seismicity region in Vancouver. The retrofitted configuration is modeled on an open source nonlinear building simulation platform. The numerical modeling and the impact modeling approach are both validated through the comparison with prior numerical and experimental results. This thesis is concerned with the amplification on the superstructure's dynamic response with the presence of poundings, which implies a potential reduction of the effectiveness of the implemented seismic retrofit system. Highly increased acceleration values that affect the building's non-structural components are recorded through nonlinear response history analyses. It is concluded that the selection of the available gap displacement between the hospital under concern and the surrounding moat walls, should take into consideration two parameters; the design displacement of the isolators and the displacement generated from the nonlinear response history analyses that minimizes pounding effects. A gap displacement between the building and the surrounding moat walls is recommended for limiting impact phenomena. This thesis provides valuable insights into the increase of the effectiveness and reliability of isolation systems in Canada during strong earthquake motions, when poundings are present." --

Download or read book Seismic Response of Base isolated Buildings written by Khaled Mohamed Amin Abdou and published by . This book was released on 1990 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design of Seismic Isolated Structures written by Farzad Naeim and published by John Wiley & Sons. This book was released on 1999-03-25 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Um die Auswirkungen von Erdbeben auf Gebäude, Brücken und andere empfindliche Konstruktionen zu mildern, wurden im Laufe der Jahre zahlreiche Technologien entwickelt. Eine der neueren hiervon ist die seismische Isolation: Sie beinhaltet den Einbau von Mechanismen, die das Gebäude von den Bewegungen des Untergrunds entkoppeln. Der Erfolg dieser Technik übertrifft den aller vorher bekannten Verfahren - ein Grund für Ingenieure und Architekten, sich genauer zu informieren. Dazu sei dieses Buch empfohlen. (04/99)

Download or read book World War Z written by Max Brooks and published by Broadway Books. This book was released on 2013 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: An account of the decade-long conflict between humankind and hordes of the predatory undead is told from the perspective of dozens of survivors who describe in their own words the epic human battle for survival, in a novel that is the basis for the June 2013 film starring Brad Pitt. Reissue. Movie Tie-In.

Download or read book Seismic Response of Base isolated Building written by Chuan Chong Ng and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Response of Base isolated Buildings Using a Viscoelastic Model written by and published by . This book was released on 1993 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Advances and Applications of Hybrid Simulation written by Wei Song and published by Frontiers Media SA. This book was released on 2021-01-13 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Response Analysis of Base isolated Secondary Systems written by Bechara Elie Samaha and published by . This book was released on 1992 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 2012 IBC SEAOC Structural seismic Design Manual Examples for concrete buildings written by Structural Engineers Association of California and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2012 IBC Structural/Seismic Design Manual provides a step-by-step approach to applying the structural provisions of the 2012 International Building Code and referenced standards. Volume 1 contains code application examples based on the IBC and ASCE 7-10 including determination of seismic irregularities, combinations of structural systems, determination of drift, support of discontinuous systems, and analysis of seismic forces applied to equipment, non-structural elements and non-building structures. Volume 2 contains code application examples of light-frame, tilt-up and masonry construction. Diaphragm flexibility, center of mass, collectors and chords, deflection and anchorage are discussed through examples. In and out-of-plane seismic loads are analyzed. Volume 3 contains code application examples of concrete construction. Moment frames, braced frames and shear wall construction are analyzed. Volume 4 contains code application examples of steel construction. Moment frames and braced frames are analyzed. Volume 5 contains examples of seismically isolated buildings and buildings with supplemental damping.

Download or read book Enhanced Seismic Resiliency for Buildings Via Base Isolation written by Michelle Carolyn Chen and published by . This book was released on 2018 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Base isolation is an effective technology for reducing seismic damage to both structural and nonstructural components, as well as to building contents, allowing buildings to remain functional during and in the aftermath of a rare and strong intensity earthquake. This makes it an ideal seismic response modification system for hospitals and buildings of high importance. Despite the enhanced seismic resiliency of buildings incorporating base isolation, many countries have been slow to adopt it in building designs prior to experiencing the devastating effects of a major earthquake, often embracing the technology as an outcome. The goal of the research in this dissertation is to advance the understanding of base isolation, in order to diminish some of the barriers that impede its widespread use. This dissertation uses data collected from a shake table experiment of a full-scale five-story building outfitted with nonstructural components and systems to analyze the structural response of the building in both base isolated and fixed base configurations. By simulating a realistic environment, this project documents the destructive effects of an earthquake with and without base isolation, ultimately demonstrating the technology's effectiveness in minimizing structural demands. Another test that was conducted addressed the specific response of an isolator in realistic earthquake conditions. One of the barriers that prevents the use of base isolation in certain scenarios is because of gaps in knowledge due to lack of testing. To address this, a comprehensive multiaxial testing program of a high damping rubber bearing was performed, fully characterizing the bearing in six degrees of freedom, to understand the impact of realistic loading conditions on the isolator response. Finally, base isolation is often implemented in buildings specifically to protect nonstructural components and ensure functionality of the building after an earthquake. Despite this, current design codes do not specifically address nonstructural components within base isolated buildings. This dissertation proposes a framework for designing inertia-sensitive nonstructural components within base isolated buildings. The framework is demonstrated through a case study using experimental structural response data in conjunction with simulated nonstructural responses generated by relative displacement floor response spectra for inelastic response.