Download or read book Seismic Response of Buildings that Utilise Unbonded Post Tensioned Concrete Walls written by Jonathan Watkins (‡c (PhD)) and published by . This book was released on 2017 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unbonded post-tensioned precast concrete walls are a low-damage seismic resisting system that resist lateral loads by rocking at the wall base. This thesis addresses the uncertainty that wall-to-floor interaction can have on the seismic response and performance of buildings that use such wall systems. A computational model was developed and verified to accurately calculate the bi-directional lateral-load response of isolated post-tensioned concrete walls. The wall model was extended to represent a previously tested full scale, four storey building with post-tensioned concrete walls. The building model accurately captured the measured response of the test building that was subjected to increasing intensities of earthquake motion on a tri-directional shake-table. To accurately capture the seismic response of the building the model must represent the in-plane and out-of-plane floor behaviour, account for cracking of the floor, and represent the stiffness of the precast concrete floor units. Wall-to-floor interaction resulted in deformations that were concentrated in the link slab between the wall and adjacent precast floor unit of the test building. This deformation resulted in significant over-strength demands on the wall and column, which the dynamic loading further increased. During the 1995 Kobe earthquake motion the peak wall base shear from the building model was 110% greater compared to the same building model that did not account for wall-to-floor interaction or dynamic loading. A parametric study of the building model found that increasing the rib depth of the precast floor elements or the thickness of the floor resulted in significantly greater over-strength demands compared to the original building. The results of the parametric study confirmed that if the effects of wall-to-floor interaction are not considered as part of the design process, the inelastic mechanisms that develop when a building is subjected to an earthquake may be different than predicted and result in undesirable failure modes An innovative wall-to-floor connector that could eliminate the adverse effects of wall-to-floor interaction was experimentally subjected to the combination of vertical displacement and shear forces they would experience in a major earthquake. Within their design limits the connectors performed well and effectively isolated the floor from the walls vertical displacement while transferring shear force from the floor to the wall.

Download or read book Seismic Response of Unbonded Post tensioned Precast Concrete Walls with Ductile Vertical Connections written by James Roland Conley and published by . This book was released on 2000 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Response of Unbonded Post tensioned Concrete Walls for Seismic Resilient Structures written by Kimberley M. Twigden and published by . This book was released on 2016 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research in this thesis was conducted with the primary aim of advancing the current state of knowledge of unbonded Post-Tensioned (PT) precast concrete rocking walls. Emphasis was placed on systematically investigating both the static and dynamic experimental response of Single Rocking Wall (SRW) and Precast Wall with End Columns (PreWEC) systems. Using the experimental data generated, simple numerical modelling techniques were investigated and the Direct Displacement Based Design (DDBD) process was verified. The experimental programme consisted of component tests on modified energy dissipating Oconnectors and pseudo-static cyclic, snap back, and shake table testing on a selection of SRW and PreWEC systems. The unique experimental investigation into the cyclic response of an improved O-connector confirmed the suitability of the O-connector as a cost effective energy dissipater that is able to demonstrate stable hysteretic behaviour while being easy to install and replace. The focus of the wall tests was on assessing the general wall response and design, the influence of the O-connectors on the wall panel, initial stiffness and fundamental frequency, equivalent viscous damping and residual drifts from different loading types. During the wall tests only minor damage and negligible residual drifts were observed which confirmed the desirable seismic behaviour of SRW and PreWEC systems under both static and dynamic loads. An investigation was performed using a simple single degree of freedom numerical model to provide recommendations on appropriate damping schemes that are able to emulate the seismic response of SRW and PreWEC systems that were validated using the shake table test results. The numerical analyses indicated that good estimation of the seismic response could be attained when using 2% tangent stiffness proportional damping in combination with a hysteretic behaviour calibrated to the cyclic hysteresis. Lastly, an assessment of current methods used for determining the equivalent viscous damping for unbonded PT walls systems in the current DDBD framework was performed. A current method based on the weighted contribution of an unbonded PT only system and a purely dissipative system was found to produce good results when used with the proposed bilinear force-displacement idealisation based on an effective stiffness.

Download or read book Seismic Design and Response Evaluation of Unbonded Post tensioned Precast Concrete Walls written by and published by . This book was released on 1997 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Performance and Modeling of Reinforced Concrete and Post Tensioned Precast Concrete Shear Walls written by Ahmet Can Tanyeri and published by . This book was released on 2014 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Past earthquakes have shown examples of unsatisfactory performance of buildings using reinforced concrete structural walls as the primary lateral-force-resisting system. In the 1994 Northridge earthquake, examples can be found where walls possessed too much overstrength, leading to unintended failure of collectors and floor systems, including precast and post-tensioned construction. In the 2010 Maule Chile earthquake, many structural wall buildings sustained severe damage. Although Chilean design standards result in different reinforcement detailing than is common in U.S. walls, the failure patterns raise concerns about how well conventionally reinforced structural walls in U.S. buildings will perform during the next earthquake. Alternative wall design philosophies that offer more predictable response, with better damage control, should be investigated. After the Mw 8.8 Chile earthquake, the 15-story Alto Rio building in Concepción sustained failures near the base, overturned, and came to rest on its side. The collapse of the Alto Rio building was significant because it was designed using the Chilean Building Code NCh433. Of96, which requires the use of ACI 318-95 for design of reinforced concrete structural elements intended to resist design seismic forces. The failure of the Alto Rio building is significant for many reasons. It is the first modern shear wall building of its type to collapse by overturning during an earthquake. The building is studied using forensic data and structural models of the framing system subjected to earthquake shaking. The study identifies the likely failure mechanism and suggests areas for which design and detailing practices could be improved. The capabilities and shortcomings of the analyses to identify details of the failure mechanism are themselves important outcomes of the study. A second study explores the behavior of structural wall buildings using unbonded post-tensioned structural walls. Such walls offer the opportunity to better control yielding mechanisms and promote self-centering behavior. The study focuses on the measured responses of a full-scale, four-story building model tested on the E-Defense shaking table in Japan. The seismic force-resisting system of the test building comprised two post-tensioned (PT) precast frames in one direction and two unbonded PT precast walls in the other direction. The building was designed using the latest code requirements and design recommendations available both in Japan and the U.S., including the ACI ITG-5.2-09. The test building was subjected to several earthquake ground motions, ranging from serviceability level to near collapse. Analytical studies were carried out to test the capability of the structural models to replicate behaviors important to structural engineers, and to assess whether available analysis tools are sufficient to model dynamic behavior that results when a full-scale building is subjected to realistic earthquake ground shaking. Measured response data from such an outstanding test provides an opportunity to fully understand the response characteristics of PT walls and assess the ability of nonlinear analytical models to reproduce important global and local responses, including three-dimensional system interactions, both prior to and after loss of significant lateral strength. Moreover, this study to assess behavior and system interaction of PT walls leads to improvements of the current design ideas and performance expectations. The present study examines both the collapse of the Alto Rio building in Chile and the shaking table tests of the unbonded post-tensioned wall building in Japan. The collapse study suggests areas of improvement in current design and detailing practice. The shaking table study suggests an alternative approach to design of shear walls in buildings. Both studies demonstrate the use of modern structural analysis tools to interpret building responses to earthquake shaking. Taken together, the studies provide added confidence in earthquake simulation capabilities and demonstrate alternatives for designing earthquake-resistant buildings that use structural walls.

Download or read book Seismic Analysis Behavior and Design of Unbonded Post tensioned Precast Concrete Walls written by Yahya Cüneyt Kurama and published by . This book was released on 1997 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic Analysis and Design of Buildings Equipped with Propped Rocking Wall Systems written by Afsoon Nicknam and published by . This book was released on 2015 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Propped Rocking Wall (PRW) is an innovative technology which combines passive damping with unbonded post-tensioned rocking concrete walls. This system has been proposed to reduce economic losses associated with earthquakes by returning a building to a functional state following a design seismic event. The proposed seismic force-resisting system consists of a slender unbonded post-tensioned concrete wall which is "propped" near the top with multi-story diagonal steel braces equipped with passive supplemental damping devices. In this study, a closed-form solution was derived for the global hysteretic response of the PRW system and a parametric study was conducted to evaluate the effect of different structural parameters involved. A seismic Direct Displacement-Based Design (DDBD) procedure for buildings equipped with PRW systems was then developed. The proposed design procedure was first evaluated through a comparative study between the seismic performance of the introduced system as opposed to a similar system called Propped Shear Walls (PSW) from which the proposed system was originally inspired. The adequacy of the proposed DDBD procedure and further the performance of PRWs were then evaluated through a shake table testing program. Detailed modeling of the PRW test model was developed and validated with shake table test results. Numerical modeling of the PRW on the prototype scale was further adopted and used in a seismic vulnerability assessment study based on the Methodology presented in FEMA P695. Design verifications were then extended to taller buildings equipped with the proposed Propped Rocking Wall (PRW) system. For this purpose, the seismic response of an 8-story building was evaluated against the predetermined performance objectives set in the beginning of the design procedure. In addition, the sensitivity of the response parameters under consideration to three main design parameters was studied.

Download or read book Design of Reinforced Concrete Buildings for Seismic Performance written by Mark Aschheim and published by CRC Press. This book was released on 2019-04-05 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: The costs of inadequate earthquake engineering are huge, especially for reinforced concrete buildings. This book presents the principles of earthquake-resistant structural engineering, and uses the latest tools and techniques to give practical design guidance to address single or multiple seismic performance levels. It presents an elegant, simple and theoretically coherent design framework. Required strength is determined on the basis of an estimated yield displacement and desired limits of system ductility and drift demands. A simple deterministic approach is presented along with its elaboration into a probabilistic treatment that allows for design to limit annual probabilities of failure. The design method allows the seismic force resisting system to be designed on the basis of elastic analysis results, while nonlinear analysis is used for performance verification. Detailing requirements of ACI 318 and Eurocode 8 are presented. Students will benefit from the coverage of seismology, structural dynamics, reinforced concrete, and capacity design approaches, which allows the book to be used as a foundation text in earthquake engineering.

Download or read book Advances in Seismic Performance and Risk Estimation of Precast Concrete Buildings written by Andrea Belleri and published by Frontiers Media SA. This book was released on 2022-02-09 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Building Technology written by M. Anson and published by Elsevier. This book was released on 2002-11-14 with total page 1844 pages. Available in PDF, EPUB and Kindle. Book excerpt: This set of proceedings is based on the International Conference on Advances in Building Technology in Hong Kong on 4-6 December 2002. The two volumes of proceedings contain 9 invited keynote papers, 72 papers delivered by 11 teams , and 133 contributed papers from over 20 countries around the world. The papers cover a wide spectrum of topics across the three technology sub-themes of structures and construction, environment, and information technology. The variety within these categories spans a width of topics, and these proceedings provide readers with a good general overview of recent advances in building research.

Download or read book NEHRP Commentary on the Gidelines for the Seismic Rehabilitation of Buildings written by Eugene Zeller and published by DIANE Publishing. This book was released on 2000-06 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document from the National Earthquake Hazards Reduction Program (NEHRP) was prepared for the Building Seismic Safety Council (BSSC) with funding from the Federal Emergency Management Agency (FEMA). It provides commentary on the NEHRP Guidelines for the Seismic Rehabilitation of Buildings. It contains systematic guidance enabling design professionals to formulate effective & reliable rehabilitation approaches that will limit the expected earthquake damage to a specified range for a specified level of ground shaking. This kind of guidance applicable to all types of existing buildings & in all parts of the country has never existed before. Illustrated.

Download or read book Analytical Modeling and Lateral Load Behavior of Unbonded Post tensioned Precast Concrete Walls written by and published by . This book was released on 1998 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Earthquake Resistant Engineering Structures IX written by C. A. Brebbia and published by WIT Press. This book was released on 2013-07-08 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: In earthquake-prone regions of the world it is important not only to ensure that new facilities meet optimal standards but also that existing structures and infrastructure be retrofitted and rehabilitated. As world populations concentrate in urban areas, the stakes in human life and property of such natural disasters as earthquakes becomes higher and higher. This has been driving research on advances in the field. These advances are presented biennially at a conference organised by the Wessex Institute of Technology.The advances presented at the ninth conference in the series, which began in 1991 are presented in this book. The papers cover Plates and other geological risks; Earthquake prediction; Microzoning; Remote sensing / Monitoring / Early warning systems; Seismic codes; Seismic hazard and vulnerability; Tsunamis; Seismic isolation and energy dissipation; Structural dynamics; Building performance during earthquakes; Retrofitting; Lifelines; Material mechanics and characterisation; Nonlinear numerical analysis; Performance based design; Experimental studies; Forensic analysis; Safety and security; Socio-economic issues; Insurance related issues; Innovative technologies; Case studies.

Download or read book Seismic Response of Simple Precast Concrete Walls written by Armand Youssef Zouein and published by . This book was released on 1980 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of 17th Symposium on Earthquake Engineering Vol 1 written by Manish Shrikhande and published by Springer Nature. This book was released on 2023-08-28 with total page 769 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents select proceedings of the 17th Symposium on Earthquake Engineering organized by the Department of Earthquake Engineering, Indian Institute of Technology Roorkee. The topics covered in the proceedings include engineering seismology and seismotectonics, earthquake hazard assessment, seismic microzonation and urban planning, dynamic properties of soils and ground response, ground improvement techniques for seismic hazards, computational soil dynamics, dynamic soil–structure interaction, codal provisions on earthquake-resistant design, seismic evaluation and retrofitting of structures, earthquake disaster mitigation and management, and many more. This book also discusses relevant issues related to earthquakes, such as human response and socioeconomic matters, post-earthquake rehabilitation, earthquake engineering education, public awareness, participation and enforcement of building safety laws, and earthquake prediction and early warning system. This book is a valuable reference for researchers and professionals working in the area of earthquake engineering.

Download or read book Analysis and Validation of a Seismic Design Method Proposed for Precast Jointed Wall Systems written by Derek James Thomas and published by . This book was released on 2003 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following the satisfactory response of the unbonded post-tensioned precast concrete wall system tested for seismic performance as part of the PREcast Seismic Structural Systems (PRESSS) test building, a set of design guidelines was published. The primary objective of this research is to evaluate the adequacy of the design guidelines and make appropriate recommendations so that the guidelines can be adopted for design of jointed walls in seismic regions. The test data to date on such systems are those collected during the wall direction testing of the PRESSS test building. Hence, this data set has been employed in the validation process. Furthermore, in order to validate the design guidelines over a range of lateral drift levels, an analytical procedure was first developed by reversing the suggested guidelines. Additionally, because of the shortcomings associated with the use of the equivalent stress block concept in design, an alternative analysis method was also considered, which was based on the monolithic beam analogy recommended for jointed systems. The analytical results from monotonic loading were compared to experimental response of the wall established from the PRESSS test building. It was found that both the analysis methods based on PRESSS and MBA predicted the moment response of the wall adequately. However, utilizing the PRESSS guidelines it was found that the neutral axis depth was overestimated by over 100% and the post-tensioning elongation was underestimated by 26%. It was also revealed that the frame contributed to the moment resistance in the wall direction by as much as 25%.

Download or read book Proceedings of the 9th International Conference on Civil Engineering written by Guangliang Feng and published by Springer Nature. This book was released on 2023-06-17 with total page 627 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book is a compilation of selected papers from the 9th International Conference on Civil Engineering (ICCE2022). The work focuses on novel research findings on seismic technology of civil engineering structures, High-tech construction materials, digitalization of civil engineering, urban underground space development. The contents make valuable contributions to academic researchers and engineers.