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1
Phansalkar, Nachiket S. "Seismic Substructure Design Workbook." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1220554481.
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Nishiyama, Minehiro. "Seismic Response and Seismic Design of Prestressed Concrete Building Structures." Kyoto University, 1993. http://hdl.handle.net/2433/74644.
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Klopp, Gregory Mark. "Seismic design of unreinforced masonry structures /." Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phk658.pdf.
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4
Castillo, Rolando. "Seismic design of asymmetric ductile systems." Thesis, University of Canterbury. Department of Civil Engineering, 2004. http://hdl.handle.net/10092/5055.
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The research promotes a better understanding of the response of torsionally unrestrained and
restrained ductile systems by examining the mechanism developed during the torsional response
of systems as they are affected by the dynamic actions of the translational and rotational mass.
A simple but effective design strategy for the seismic design of torsionally asymmetric systems
is suggested based on the estimate of the system displacement ductility capacity and the
distribution of the estimated system strength to its elements. The strength eccentricity is
considered the main parameter to influence the ductile response of asymmetric systems.
The possible success of the design strategy to limit displacement demands of the elements to less
than their displacement ductility capacity, for zero and increasing strength eccentricities, was
examined against the effects of key parameters expected to influence response. These
parameters are: strength eccentricity and the associated increase of system strength, mass
eccentricity, ratio of radii of gyration of strength and mass, reduced system displacement
ductility capacity, transverse elements and their degree of torsional restraint, the ratio of element
nominal yield displacement, i.e., α=Δye2/Δye1. and associated stiffness eccentricity, uncoupled
translational period, consideration of different earthquake records and their direction of
application.
Elements are modelled with a realistic relationship between element strength, stiffness and
nominal yield displacement. The stiffness is strength dependant and the nominal yield
displacement is a geometric and material property independent of strength. The centre of
strength and stiffness are, therefore, not independent parameters.
This research focuses on analytical studies of torsionally unrestrained and restrained single-mass
asymmetric systems. Single, two and multi-element systems were examined. An experimental
programme was also undertaken on single-mass models to verify some of the analytical findings.
The findings suggest that the suggested design strategy is successful in limiting the displacement
demands on elements to less than their displacement capacity for zero and increasing strength
eccentricities. No differentiation is required between systems having or not having mass
eccentricity. The proposed design strategy is slightly different for torsionally unrestrained and
restrained systems. It promises to be straightforward, rational and in terms of design efforts most
user friendly.
5
Lim, Tim S. "High-performance braces for seismic design." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82715.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2013.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (p. 73-79).<br>The fundamental challenge for the structural engineer in designing earthquake-resistant structures is to design buildings with both adequate ductility and sufficient stiffness. Traditional lateral force resisting systems such as the moment resisting frame and the concentrically braced frame are both conventional structural schemes that have been implemented for many years, but result in only mediocre performance levels. The lacking stiffness of a moment resisting frame as well as the limited ductility of a concentrically braced frame gave impetus for engineers to direct significant research efforts into the development of new lateral resisting systems that embody a more stable hysteretic behavior, adequate ductility, control of damage, and energy dissipating capacity. Fortunately, several recent developments have allowed engineers to move one step closer to designing more efficient earthquake-resistant structures. "High-performance braces," as this thesis calls them, are new and improved bracing systems that combine the economy and stiffness of a concentrically braced frame with the ductility and energy dissipating capacity of a moment resisting frame. This thesis analyzes and evaluates three different types of high-performance braces: (i) the buckling-restrained brace frame, (ii) the self-centering energy dissipating brace frame, and (iii) the hybrid brace frame, with regards to their structural performance and economy. The primary goal of the thesis is to provide useful insights into the current developments of high-performance braces for practicing engineers in the hope that such systems can be more widely adopted and utilized in the contemporary design of earthquake-resistant structures. Keywords: High-performance braces, earthquake-resistant structures, seismic design<br>by Tim S. Lim.<br>M.Eng.
6
Tsertikidou, Despoina. "Evaluation of strategies for seismic design." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/74414.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 57-58).<br>Current trends in seismic design require a new approach, oriented in satisfying motion related design requirements and limiting both structural and non-structural damage. Seismic isolation and damping devices are currently used in buildings as two innovative performance-based design approaches. This thesis explores the effectiveness and the differences of the two methods in mitigating the motion of buildings when subjected to earthquake excitation. The concept, advantages, constraints and limitations of the implementation of these two methods are discussed. Major types of isolators and damping devices are presented. A comparative analysis of the seismic response of a fixed base structure, a base isolated and a structure with damping devices is performed with the use of SAP2000.<br>by Despoina Tsertikidou.<br>M.Eng.
7
Celikbas, Ayse 1974. "Economics of damage controlled seismic design." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80487.
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Luis, Alberto Bedriñana Mera. "SEISMIC PERFORMANCE AND SEISMIC DESIGN OF DAMAGE-CONTROLLED PRESTRESSED CONCRETE BUILDING STRUCTURES." Kyoto University, 2018. http://hdl.handle.net/2433/235084.
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Martin, David N. "Evaluation and comparison of a non-seismic design and seismic design for a low rise office building." Master's thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-03172010-020113/.
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Valenzuela-Beltrán, Federico, Sonia Ruiz, Alfredo Reyes-Salazar, and J. Gaxiola-Camacho. "On the Seismic Design of Structures with Tilting Located within a Seismic Region." MDPI AG, 2017. http://hdl.handle.net/10150/626403.
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A reliability-based criterion to estimate strength amplification factors for buildings with asymmetric yielding located within a seismic region presenting different soil conditions is proposed and applied. The approach involves the calculation of the mean annual rate of exceedance of structural demands of systems with different levels of asymmetric yielding. Two simplified mathematical expressions are developed considering different soil conditions of the valley of Mexico. The mathematical expressions depend on the ductility of the structural systems, their level of asymmetric yielding, their fundamental vibration period and the dominant period of the soil. In addition, the proposed expressions are compared with that recommended by the current Mexico City Building Code (MCBC). Since the expressions are developed with the help of simplified structural systems, the validity of such expressions is corroborated by comparing the expected ductility demand of multi-degree of freedom (MDOF) structural systems with respect to that of their equivalent simplified systems. Both structural representations are associated with a given annual rate of exceedance value of an engineering demand parameter. The expressions proposed in this study will be incorporated in the new version of the MCBC.
11
Tuken, Ahmet. "Quantifying Seismic Design Criteria For Concrete Buildings." Phd thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/12604907/index.pdf.
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The amount of total and relative sway of a framed or a composite (frame-shear wall) building is of utmost importance in assessing the seismic resistance of the building. Therefore, the design engineer must calculate the sway profile of the building several times during the design process.
However, it is not a simple task to calculate the sway of a three-dimensional structure. Of course, computer programs can do the job, but developing the three-dimensional model becomes necessary, which is obviously tedious and time consuming.
An easy to apply analytical method is developed, which enables the determination of sway profiles of framed and composite buildings subject to seismic loading. Various framed and composite three-dimensional buildings subject to lateral seismic loads are solved by SAP2000 and the proposed analytical method. The sway profiles are compared and found to be in very good agreement. In most cases, the amount of error involved is less than 5 %.
The analytical method is applied to determine sway magnitudes at any desired elevation of the building, the relative sway between two consecutive floors, the slope at any desired point along the height and the curvature distribution of the building from foundation to roof level.
After sway and sway-related properties are known, the requirements of the Turkish Earthquake Code can be evaluated and / or checked.
By using the analytical method, the amount of shear walls necessary to satisfy Turkish Earthquake Code requirements are determined. Thus, a vital design question has been answered, which up till present time, could only be met by rough empirical guidelines.
A mathematical derivation is presented to satisfy the strength requirement of a three-dimensional composite building subject to seismic loading. Thus, the occurrence of shear failure before moment failure in the building is securely avoided.
A design procedure is developed to satisfy the stiffness requirement of composite buildings subject to lateral seismic loading. Some useful tools, such as executable user-friendly programs written by using &ldquo<br>Borland Delphi&rdquo<br>, have been developed to make the analysis and design easy for the engineer.
A method is also developed to satisfy the ductility requirement of composite buildings subject to lateral seismic loading based on a plastic analysis. The commonly accepted sway ductility of &<br>#956<br>&<br>#916<br>=5 has been used and successful seismic energy dissipation is thus obtained.
12
Haque, A. B. M. Rafiqul. "Seismic design of industrial rack clad buildings." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42326.
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Rack clad building (RCB) is a type of warehouse building system built using steel storage racks. Generally, these structures are larger and taller compared to regular storage racks commonly seen in superstores. These are built in a way that the peripheral frame can be used to support cladding. These structures possess some unique properties such as the members are built using thin walled perforated steel sections and the beam column joints utilizes teardrop connector in down isle direction. The hysteretic behavior of these connections is usually pinched type. Due to these properties the structure shows unique behavior under lateral loading. Until now very little research work has been carried out to determine the seismic performance of these structures. As RCB is a new type of structure, there exists no guideline in the current building codes for designing these structures against seismic loading. Here, a force and a direct displacement based design (DDBD) procedure have been adapted for designing RCB structures in the down isle direction. Finally, the performances of RCB frames designed under these two different methods have been compared and an optimum design method has been recommended for such type of structures.
13
Ozel, Alperen. "Seismic Design of a Prestressed Concrete Bridge." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2181.
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Latest advancements in software have become an indispensable tool in structural analysis. The main goal of this thesis is to examine dynamic responses of bridges in seismic activity with the help of such tool as CSi Bridge. Therefore, throughout this study, a prestressed concrete bridge model will be thoroughly designed. In the first section, the required materials and structural components will be introduced. The following section will cover calculations required for modeling. The actual modeling of the structure will be carried out in Section 3. In Section 4, the set of required analysis for seismic design such as modal, pushover and response spectrum will be conducted. Lastly, in Section 5, analysis results will be evaluated. Thus, by examining the entire model, its construction, materials used, provided properties and conditions such as location on earth, seismic magnitude, it will be determined whether the design is sufficient and acceptable or not.
14
Shelman, Aaron Trask. "Seismic design of drilled shafts in clay." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1473259.
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Loss, Cristiano. "Displacement-Based Seismic Design of Timber Structures." Doctoral thesis, Università degli studi di Trento, 2011. https://hdl.handle.net/11572/369244.
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The research is aimed at developing seismic methods for the design and evaluation of the seismic vulnerability of wooden structures, using a displacement-based approach. After a brief introduction on the seismic behaviour of timber structures, the general Direct Displacement-Based Design (Direct-DBD) procedure and the state-of-the-art are presented, with clear reference to the application of the Direct-DBD method to wooden buildings. The strength of the Direct-DBD method is its ability to design structures in a manner consistent with the level of damage expected, by directly relating the response and the expected performance of the structure. The research begins with a description of the procedural aspects of the Direct-DBD method and the parameters required for its application.
The research presented focuses on the formulation of a displacement-based seismic design procedure, applicable to one-storey wooden structures made with a portal system. This typology is very common in Europe and particularly in Italy. A series of analytical expressions have been developed to calculate design parameters. The required analytical Direct-DBD parameters are implemented based on the mechanical behaviour of the connections, made with metal dowel-type fasteners. The calibration and subsequent validation of design parameters use a Monte Carlo numerical simulation and outcomes obtained by tests in full-scale.
After the description of the Displacement-Based method for one-storey wooden structures, a series of guidelines to extend the Direct-DBD methodology to other types and categories of timber systems are proposed. The thesis presents the case of a multi-storey wood frame construction, which is a simple extension of the glulam portal frame system.
Part of this work has been done within the RELUIS Project, (REte dei Laboratori Universitari di Ingegneria Sismica), Research Line IV, which in the years between 2005 and 2008 involved several Italian universities and Italian institutes of research in the development of new seismic design methods. The Project produced the first draft of model code for the seismic design of structures based on displacement (Direct-DBD). This thesis is the background to the section of the model code developed for timber structures.
16
Loss, Cristiano. "Displacement-Based Seismic Design of Timber Structures." Doctoral thesis, University of Trento, 2011. http://eprints-phd.biblio.unitn.it/593/1/PHD_THESIS_C_LOSS_DEPOSITO.pdf.
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The research is aimed at developing seismic methods for the design and evaluation of the seismic vulnerability of wooden structures, using a displacement-based approach. After a brief introduction on the seismic behaviour of timber structures, the general Direct Displacement-Based Design (Direct-DBD) procedure and the state-of-the-art are presented, with clear reference to the application of the Direct-DBD method to wooden buildings. The strength of the Direct-DBD method is its ability to design structures in a manner consistent with the level of damage expected, by directly relating the response and the expected performance of the structure. The research begins with a description of the procedural aspects of the Direct-DBD method and the parameters required for its application.
The research presented focuses on the formulation of a displacement-based seismic design procedure, applicable to one-storey wooden structures made with a portal system. This typology is very common in Europe and particularly in Italy. A series of analytical expressions have been developed to calculate design parameters. The required analytical Direct-DBD parameters are implemented based on the mechanical behaviour of the connections, made with metal dowel-type fasteners. The calibration and subsequent validation of design parameters use a Monte Carlo numerical simulation and outcomes obtained by tests in full-scale.
After the description of the Displacement-Based method for one-storey wooden structures, a series of guidelines to extend the Direct-DBD methodology to other types and categories of timber systems are proposed. The thesis presents the case of a multi-storey wood frame construction, which is a simple extension of the glulam portal frame system.
Part of this work has been done within the RELUIS Project, (REte dei Laboratori Universitari di Ingegneria Sismica), Research Line IV, which in the years between 2005 and 2008 involved several Italian universities and Italian institutes of research in the development of new seismic design methods. The Project produced the first draft of model code for the seismic design of structures based on displacement (Direct-DBD). This thesis is the background to the section of the model code developed for timber structures.
17
Yang, Dong-Shan. "Deformation-based seismic design models for waterfront structures." Thesis, online access from Digital Dissertation Consortium access full-text, 1999. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?9933214.
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Acikgoz, Mehmet Sinan. "Seismic assessment of flexible rocking structures." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708891.
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Ramanathan, Karthik Narayan. "Next generation seismic fragility curves for california bridges incorporating the evolution in seismic design philosophy." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44883.
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Quantitative and qualitative assessment of the seismic risk to highway bridges is crucial in pre-earthquake planning, and post-earthquake response of transportation systems. Such assessments provide valuable knowledge about a number of principal effects of earthquakes such as traffic disruption of the overall highway system, impact on the regions' economy and post-earthquake response and recovery, and more recently serve as measures to quantify resilience. Unlike previous work, this study captures unique bridge design attributes specific to California bridge classes along with their evolution over three significant design eras, separated by the historic 1971 San Fernando and 1989 Loma Prieta earthquakes (these events affected changes in bridge seismic design philosophy). This research developed next-generation fragility curves for four multispan concrete bridge classes by synthesizing new knowledge and emerging modeling capabilities, and by closely coordinating new and ongoing national research initiatives with expertise from bridge designers.
A multi-phase framework was developed for generating fragility curves, which provides decision makers with essential tools for emergency response, design, planning, policy support, and maximizing investments in bridge retrofit. This framework encompasses generational changes in bridge design and construction details. Parameterized high-fidelity three-dimensional nonlinear analytical models are developed for the portfolios of bridge classes within different design eras. These models incorporate a wide range of geometric and material uncertainties, and their responses are characterized under seismic loadings. Fragility curves were then developed considering the vulnerability of multiple components and thereby help to quantify the performance of highway bridge networks and to study the impact of seismic design principles on the performance within a bridge class. This not only leads to the development of fragility relations that are unique and better suited for bridges in California, but also leads to the creation of better bridge classes and sub-bins that have more consistent performance characteristics than those currently provided by the National Bridge Inventory. Another important feature of this research is associated with the development of damage state definitions and grouping of bridge components in a way that they have similar consequences in terms of repair and traffic implications following a seismic event. These definitions are in alignment with the California Department of Transportation's design and operational experience, thereby enabling better performance assessment, emergency response, and management in the aftermath of a seismic event. The fragility curves developed as a part of this research will be employed in ShakeCast, a web-based post-earthquake situational awareness application that automatically retrieves earthquake shaking data and generates potential damage assessment notifications for emergency managers and responders.<br>Errata added at request of advisor and approved by Graduate Office, March 15 2016.
20
FAKHOURI, Muhannad Yacoub. "Application of Sliding Isolation Bearings with Upward Lifting Mechanism for Seismic Performance Enhancement of Multi-Story Structures." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157552.
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Broderick, Brian Michael. "Seismic testing, analysis and design of composite frames." Thesis, Imperial College London, 1994. http://hdl.handle.net/10044/1/7366.
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Atkinson, Jeremy Charles Harry. "Seismic design of outrigger systems for tall buildings." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61271.
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Outrigger systems are an effective structural scheme that is commonly used in high-rise construction to increase stiffness and distribute the moment demand within the core to the exterior columns. Despite the on-going use of outrigger structural systems around the world, a formal seismic design procedure for outrigger system is missing. This thesis presents an equivalent energy-based design procedure (EEDP) to design outrigger systems for seismic applications. Using the concept of an energy balance, elastic single-degree of freedom systems are equated to equivalent nonlinear systems, and plastic mechanisms are used to derive design forces for the outrigger systems. EEDP allows engineers to design the outrigger-wall buildings to achieve different performance objectives at different seismic hazard levels, which is desirable for creating earthquake-resilient buildings. Three prototype outrigger-wall buildings of various heights were designed using the proposed procedure for a hypothetical site in Vancouver, Canada. Detailed finite element models were developed using OpenSees to assess the seismic performance of the prototype buildings. The results of the nonlinear time history analyses show that the prototypes can meet the performance objectives specified during the design procedure. Lastly, incremental dynamic analyses were conducted using the FEMA P695 methodology to quantify the seismic safety of outrigger systems designed using EEDP. The results show that the proposed EEDP is an effective method to design outrigger systems, where the structure can achieve sufficient margin of safety against collapse and satisfy multiple performance objectives at different hazard levels without iteration.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
23
Lu, Yang. "Seismic soil-structure interaction in performance-based design." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33704/.
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Soil-Structure Interaction (SSI) procedures for performance-based seismic design of building structures have been in existence in design guidelines and provisions for decades. However, several issues still remain regarding the application of these procedures to inelastic multi-storey buildings. Three main issues are identified and investigated in this research. Firstly, the gap between code-specified design response spectra and base shear demands of inelastic flexible-base multi-storey buildings is bridged by introducing a strength reduction factor RF and a Multi-Degree-Of-Freedom (MDOF) modification factor RM. The strength reduction factor RF, derived based on the combined (and similar) effects of SSI and structural yielding, allows base shear demands of a flexible-base yielding Single-Degree-Of-Freedom (SDOF) structure to be calculated directly from code design response spectra. The MDOF modification factor RM links base shear demand of a MDOF structure to that of its SDOF counterpart. Secondly, the effect of frequency content of ground motions on elastic and inelastic flexible-base buildings located on very soft soil profiles is examined. Results showed that normalising the equivalent period of a SSI system Tssi by the corresponding predominant periods resulted in more rational spectra for seismic design purposes. In the elastic response spectra, Tssi is normalised by the spectrum predominant period TP corresponding to the peak ordinate of a 5% damped elastic acceleration spectrum, while for nonlinear structures Tssi should be normalised by the predominant period of the ground motion, Tg, at which the relative velocity spectrum reaches its maximum value. It is shown that an actual SSI system can be replaced by an equivalent fixed-base SDOF (EFSDOF) oscillator having a natural period of Tssi, a viscous damping ratio xissi and a global ductility ratio of mussi. The EFSDOF oscillator performed well for linear systems while, in general, overestimated ductility reduction factor Rmu of SSI systems with high initial damping ratio, which consequently led to an underestimation of inelastic displacement ratio Cmu. The two issues stated above were addressed by results of a large number of response history analyses performed using a simplified SSI model where the foundation response was assumed to be linearly elastic and frequency-dependent. The soil-foundation model, developed on the basis of the cone theory, has been verified to be a reliable tool for simulating dynamic soil-foundation interaction. Finally, in order to take into account foundation nonlinearity in preliminary seismic design of building structures, a simplified nonlinear sway-rocking model was developed. The proposed model is intended to capture the nonlinear load-displacement response of shallow foundations during strong earthquake events where foundation bearing capacity is fully mobilised. Emphasis is given to heavily-loaded structures resting on a saturated clay half-space. The variation of soil stiffness and strength with depth, referred to as soil non-homogeneity, is considered in the model. Although independent springs are utilised for each of the swaying and rocking motions, coupling between these motions is taken into account by expressing the load-displacement relations as functions of the factor of safety against vertical bearing capacity failure (FSV) and the moment-to-shear ratio (M/H). The simplified model is calibrated and validated against results from a series of static push-over and dynamic analyses performed using a more rigorous finite-difference numerical model. Despite some limitations of the current implementation, the concept of this model gives engineers more degrees of freedom in defining their own model components, providing a good balance between simplicity, flexibility and accuracy.
24
Das, Satrajit. "Seismic Design of Vertically Irregular Reinforced Concrete Structures." NCSU, 2000. http://www.lib.ncsu.edu/theses/available/etd-20000820-165307.
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<p>Seismic building codes, such as the Uniform Building Code (UBC) do not allow the equivalent lateral force (ELF) procedure to be used for structures with vertical irregularities. The UBC defines a structure to be irregular based on the ratio of magnitudes of either strength, stiffness, mass, setback or offset of one floor to that of an adjacent floor. The criteria defining the limits of irregularity are somewhat arbitrary, but are introduced in the code to provide unambiguous, enforceable provisions. The purpose of this study is to quantify the definition of irregular structures for four different vertical irregularities - stiffness, strength, mass and nonstructural masonry infills. A total of 87 building structures with interstory stiffness and strength ratios ranging from 0.09 to 1.89 and 0.27 to 1.07, respectively, and mass ratios of 1.0, 2.5, and 5.0 are considered for a detailed parametric study. The lateral force resisting systems (LFRS) considered are special moment resisting frames and shear walls. These LFRS's are designed based on the forces obtained from the equivalent lateral force procedure. An ELF) analysis. Finally, nonlinear dynamic analysis is performed in order to assess the seismic performance of these buildings. The results show that the restrictions on the applicability of the equivalent lateral force procedure are unnecessarily conservative for irregular structures. Most structures considered in this study, designed on the basis of the ELF approach, perform reasonably well. In some cases, however, there is an initiation of an undesirable collapse mechanism. It is recommended that capacity based criteria in the design phase be appropriately used in the vicinity of the irregularity in order to ensure desired performance and behavior.<P>
25
Stewart, Wayne. "The seismic design of plywood sheathed shear walls." Thesis, University of Canterbury. Department of Civil Engineering, 1987. http://hdl.handle.net/10092/2458.
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A design methodology for earthquake resistant plywood sheathed shear walls
is presented. The sheathing nailing is selected as the ductile load
limiting element, whereby the large displacement demands imposed during an
earthquake can be sustained without failure of the timber members in
bending, shear or tension. Analytical models for predicting the elastic
behaviour and ultimate strength of shear walls are formulated in order to
develop the design procedure.
An experimental study of nailed sheathed joints was undertaken, and showed
that such joints were able to sustain large reverse cycles well into the
inelastic range. Complementary to the experimental study, an analytical
strength model for nailed joints is described, and identifies nail
diameter, nail length and nail coating as being the variables most
influential on joint strength.
Eleven full scale plywood sheathed shear walls were subjected to reverse
cyclic quasi-static loading and shaketable excitation. The performance of
the sheathing nailing, framing connections and anchorage connections is
reported in detail. The test walls exhibited progressive stiffness
degradation resulting in pinched hysteresis loops, prior to failure through
the nail heads pulling through the plywood, or the nail point withdrawing
from the framing.
A theoretical time-history single degree of freedom idealisation is
described to predict the dynamic response of shear walls. Theoretical
predictions compared well with the experimental shaketable behaviour of the
full scale test walls.
The displacement demands on shear walls which exhibited pinched hysteresis
loops are compared with the corresponding displacement demands on an
elastoplastic structure.
26
Sadashiva, Vinod Kota. "Quantifying structural irregularity effects for simple seismic design." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2010. http://hdl.handle.net/10092/5309.
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This study was initiated to quantify the effect of different degrees of irregularity on
structures designed for earthquake using simplified analysis. The types of irregularity
considered were:
(a) Vertical Irregularity
• Mass
• Stiffness -Strength
(b) Horizontal (Plan) Irregularity
• Diaphragm Flexibility
Simple models were used to allow many analyses to be conducted in a relatively short
time. For vertical irregularity studies, simple shear-type structures were designed
according to the New Zealand design Standard, NZS1170.5, firstly as regular
structures, and then they were redesigned as irregular structures to the same target
drift. Both regular and irregular structures were then subjected to a suite of records,
and vertical irregularity effects evaluated from the difference in response. For the
flexible diaphragm effect study, simple models of structures were developed with: (a)
a rigid diaphragm assumption; and (b) a flexible diaphragm assumption. Flexible
diaphragm effects were evaluated by conducting time-history analyses and comparing
the responses of structures with rigid and flexible diaphragms. A mechanics based
approach was developed to quantify flexible diaphragm effects, which was shown to
produce consistent results with those from time-history analyses.
Relationships between the degree of irregularity and the change in behaviour were
developed. This information facilitates designers and plan checkers to rapidly
evaluate the likely effect of irregularity on structures. It provides guidance as to: (a)
when the effect of structural irregularity can be ignored, and (b) the change in
demands for different degrees of structural irregularity. The relations developed also
provide a rigorous technical basis for future regularity provisions in the NZS1170.5
and other world-wide seismic design codes.
27
Eshghi, Sassan. "Performance-based seismic design of reservoir intake towers." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265307.
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Otenti, Alexander A. (Alexander Alfred) 1981. "Design methodologies for the seismic retrofitting of bridges." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/29407.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.<br>Includes bibliographical references (p. 52-53).<br>This paper formulates an earthquake design strategy for bridges. Earthquakes can cause extreme economic damage and loss of life. Structural engineers must be conscience of earthquake slip type, earthquake proximity, and local soil properties when designing a structure. Structures subjected to near-field seismic events feel much complex motions and frequencies than those subjected to far-field events. When designing a structure in a seismic zone it is crucial that the engineer examine a sample of previous earthquake records from the region. Earthquake data is organized into response spectra, time histories, and frequency histories. Response spectra display the spectral displacement, velocity, and acceleration in terms of periods and are of the most interest to structural engineers. Once all of the data is gathered and organized it is necessary to decide on a retrofit strategy. Retrofitting involves either strengthening the bridge or shifting the period out of the power range of the earthquake. This paper demonstrates the effectiveness of shifting the period by base isolation with two case studies of isolated bridges and a design example. The design example is a continuation of the Waldo-Hancock Bridge Master of Engineering project completed in 2004 by the author, Andrea Scotti, and Richard Unruh. A side span of the bridge was modeled in SAP 2000 Nonlinear and subjected to the El Centro and Northridge earthquakes that struck California in 1940 and 1996, respectively. Those earthquakes were chosen because there are no recorded earthquakes in the state of Maine.<br>(cont.) The resulting column shears and deck displacements were compared for no isolation and multiple periods of isolation. It was found that the expected result indicated by the response spectra of the two quakes closely matched the performance of the bridge.<br>by Alexander A. Otenti.<br>M.Eng.
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Kennedy, Nicholas Edwards. "Seismic Design Manual for Interlocking Compressed Earth Blocks." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1049.
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Seismic Design Manual for Interlocking Compressed Earth Blocks
Nicholas Edwards Kennedy
This thesis presents a comprehensive seismic design manual to be used to design and construct simple Interlocking Compressed Earth Block (ICEB) structures in seismically active regions. ICEBs are earth blocks made primarily of soil and stabilized with cement. They have female and male stud mechanisms designed to interlock when stacked, eliminating the need for mortar. The blocks can accept reinforcement and grout after they are placed. While ICEB construction is similar to conventional masonry construction, current design code standards for masonry only partially capture the actual behavior of ICEB structures. This thesis seeks to supplement the existing masonry design procedures and tailor them for use with ICEBs.
Additionally, this paper presents a preliminary design of ICEB shear walls for a disaster reconstruction project in the Philippines. While many structures in Southeast Asia and the Malay Archipelago are constructed from earthen blocks, very few are engineered. Of those that are, a lack of formal design guidance specific to ICEB construction leaves most engineers and designers with conventional concrete masonry design practices, some of which are not applicable for use with ICEBs.
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Sabzehzar, Saman. "SEISMIC DESIGN AND EVALUATION OF BASE ISOLATED STEEL STORAGE RACKS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case14847725697335.
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Verma, Abhishek. "Seismic design and collapse-performance assessment of steel plate shear wall structures." Thesis, IIT Delhi, 2019. http://eprint.iitd.ac.in:80//handle/2074/8132.
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Boivin, Yannick. "New capacity design methods for seismic design of ductile RC shear walls." Thèse, Université de Sherbrooke, 2012. http://savoirs.usherbrooke.ca/handle/11143/1962.
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In order to produce economical seismic designs, the modern building codes allow reducing seismic design forces if the seismic force resisting system (SFRS) of a building is designed to develop an identified mechanism of inelastic lateral response. The capacity design aims to ensure that the inelastic mechanism develops as intended and no undesirable failure modes occur. Since the 1984 edition, this design approach is implemented in the Canadian Standards Association (CSA) standard A23.3 for seismic design of ductile reinforced concrete (RC) shear walls with the objectives of providing sufficient flexural and shear strength to confine the mechanism to the identified plastic hinges and ensure a flexure-governed inelastic lateral response of the walls. For a single regular wall, the implemented capacity design requirements assume a lateral deformation of the wall in its fundamental lateral mode of vibration, and hence aim to constrain the inelastic mechanism at the expected base plastic hinge. This design is referred to as single plastic-hinge (SPH) design. Despite these requirements, CSA standard A23.3 did not prescribe, prior to the 2004 edition, any methods for determining capacity design envelopes for flexural and shear strength design of ductile RC shear walls over their height. Only its Commentary recommended such methods. However, various studies suggested, mainly for cantilever walls, that the application of these methods could result in multistorey wall designs experiencing the formation of unintended plastic hinges at the upper storeys and a high potential of undesirable shear failure, principally at the wall base, jeopardizing the intended ductile flexural response of the wall. These design issues result from an underestimation of dynamic amplification due to lateral modes of vibration higher than the fundamental lateral mode. The 2004 CSA standard A23.3 now prescribes capacity design methods intending in part to address these design issues. Although these methods have not been assessed yet, their formulation appears deficient in accounting for the higher mode amplification effects. In this regard, this research project proposes for CSA standard A23.3 new capacity design methods, considering these effects, for a SPH design of regular ductile RC cantilever walls used as SFRS for multistorey buildings. In order to achieve this objective, first a seismic performance assessment of a realistic ductile shear wall system designed according to the 2004 CSA standard A23.3 is carried out to assess the prescribed capacity design methods. Secondly, an extensive parametric study based on sophisticated inelastic dynamic simulations is conducted to investigate the influence of various parameters on the higher mode amplification effects, and hence on the seismic force demand, in regular ductile RC cantilever walls designed with the 2004 CSA standard A23.3. Thirdly, a review of various capacity design methods proposed in the current literature and recommended by design codes for a SPH design is performed. From the outcomes of this review and the parametric study, new capacity design methods are proposed and a discussion on the limitations of these methods and on their applicability to various wall systems is presented.
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Schroeder, Brianna Lynn. "Seismic response assessment of skew highway bridges /." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1440918.
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Thesis (M.S.)--University of Nevada, Reno, 2006.<br>"December, 2006." Includes bibliographical references (leaves 183-186). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2006]. 1 microfilm reel ; 35 mm.
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Kim, Uksun. "Seismic behavior of steel joist girder structures." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/20804.
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Zaghi, Arash Esmaili. "Seismic design of pipe-pin connections in concrete bridges." abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3387806.
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Piscal, Arévalo Carlos Mario. "New design considerations for seismic isolated buildings in Colombia." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/663457.
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An important percentage of Colombian population is located in medium-to-high seismicity zones (NSR-10, 2010). Therefore, it is important to protect the buildings, principally the highly crowded ones, and those that are considered as indispensables for community attention after an earthquake event. One most successful techniques for structural protection is base (seismic) isolation; despite their obvious advantages, in Latin America (and, more specifically, in Colombia), its use is still only limited, whit a low number of isolated buildings. This situation can be due to several reasons: insufficient awareness of this technology, poor knowledge of the involved professionals (i.e. engineers) in design and construction of isolated structures, and lack of local design codes; this last circumstance, forces employing foreign regulations (ASCE 7 in the Colombian case) that do not account for the local characteristics and frequently lead to relevant cost increases. The objective of this Thesis is to promote base isolation in Colombia and other close countries; with this aim, the following tasks are performed: (i) to study and compare the requirements of different major seismic isolation regulations (Japan, China, Russia, Italy, USA, Chile, México), (ii) inside each code, to contrast the results (in terms of forces and displacements) obtained from approximated analysis methods (lateral equivalent method) and more sophisticated procedures (time-history analysis), (iii) to propose (for Colombia) damping modification factors for design spectra, and (iv) to formulate new considerations for design of isolated structures in Colombia (to be converted into a national design code).<br>La mayoría de la población colombiana se encuentra ubicada en zonas de amenaza sísmica alta e intermedia (NSR-10, 2010) por lo cual es de suma importancia la protección de las edificaciones, con una especial atención en las que albergan un considerable número de personas y aquellas que son consideradas como indispensables para la atención de la comunidad después de un evento sísmico. Dentro de las más recientes y exitosas medidas de protección de estructuras a nivel mundial, se encuentra el denominado aislamiento de base; a pesar de sus notorias ventajas, en Latinoamérica y más específicamente en Colombia, su uso es aún limitado. Lo anterior puede deberse, entre otras, a las siguientes razones: escasa divulgación en la zona de esta técnica y de las ventajas de su uso, falta del conocimiento necesario (por parte de los profesionales de la construcción) para llevar a cabo los procesos requeridos de diseño y construcción, y a la ausencia de una normativa nacional específica; esta última circunstancia es relevante, dado que la normativa internacional que se aplica en su lugar (ASCE 7 en el caso colombiano) no recoge las particulares locales y puede generar sobrecostos importantes. El objetivo final de esta investigación es consolidar el aislamiento sísmico en Colombia y en otros países próximos; para alcanzar este propósito, en esta investigación se llevan a cabo las siguientes actividades: (i) se estudian y comparan los requisitos estipulados en diferentes normativas de aislamiento sísmico desarrolladas a nivel mundial (Japón, China, Rusia, Italia, USA, Chile, México), (ii) en cada uno de estos códigos, se contrastan los resultados de fuerzas y desplazamientos obtenidos mediante métodos aproximados de análisis (Fuerza horizontal equivalente) y los resultados obtenidos mediante métodos más sofisticados (análisis dinámico cronológico), (iii) se proponen, para Colombia, factores modificadores del espectro de diseño en función del amortiguamiento, y (iv) se formulan nuevas consideraciones para el diseño de estructuras aisladas en Colombia (embrión de una normativa propia)
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Karakus, Hulya. "New Seismic Design Approaches For Block Type Quay Walls." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608584/index.pdf.
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In this study, new design approaches are introduced for the seismic design of block type quay walls after reviewing the conventional methodologies. Within the development of the new design approaches an inverse triangular dynamic
pressures distributions are applied to define both seismic earth pressures and seismic surcharge pressures. Differently from the conventional design methodology, the hydrodynamic forces are taken into consideration while dynamic forces are specified and equivalent unit weight concept is used during
the both static and dynamic calculations Compatibility of this new design approaches are tested by case studies for the site and it is seen that the numerical results are in good agreement qualitatively with field measurements.
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Zhang, Xiaoyue. "Seismic design of timber steel hybrid high-rise buildings." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61985.
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Timber-steel hybrid systems utilize timber as main construction material, but also take advantage of the ductility and stiffness that steel provides. For a novel hybrid system to gain recognition, experimental data must be supported by numerical analysis to predict its structural performance. “Finding the Forest Through the Trees” (FFTT) is one proposal for a timber-steel hybrid system using mass-timber panels as shear walls and floor slabs connected with steel header beams.
This thesis presents research to evaluate the seismic performance of the FFTT hybrid system using experimental methods, numerical modeling, and reliability analysis. The FFTT system was investigated on two levels: i) component design, and ii) system design. On the component level, the strength, stiffness, ductility, and failure mechanisms of the two key connections were evaluated experimentally. CLT (Cross Laminated Timber) wall to steel beam connection tests results demonstrated that appropriate connection layouts can lead to the desired failure mechanism while avoiding crushing of the mass-timber panels. For the hold-down connection, a modified HSK (Holz-Stahl-Komposit) assembly with high force and stiffness capacity together with ductile behaviour was proposed. On the system level, the seismic response of the FFTT system with different ductility values was investigated using nonlinear 2D and 3D models subjected to a number of ground motion acceleration records. The seismic reliability with various uncertainties was analysed in order to investigate the FFTT system from a performance based approach. Based on the results, an appropriate seismic force reduction factor specific to the FFTT system was proposed. Finally, a feasibility study confirmed the possibility of the practical application of this system. This thesis can serve as a precursor for developing design guidelines for tall wood-hybrid building systems in seismic regions.<br>Forestry, Faculty of<br>Graduate
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Liu, Qin. "A study of seismic design spectra for highway bridges." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ27001.pdf.
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Lefki, Lkhider. "Critical evaluation of seismic design criteria for steel buildings." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63980.
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Koboević, Sanda. "An approach to seismic design of eccentrically braced frames /." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36817.
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This dissertation investigates a novel approach to seismic design of eccentrically braced frames. The proposed design procedure incorporates non-linear time-history analysis directly into the design process. Member forces introduced by a chosen earthquake record are monitored throughout the time history, and the frame elements are selected so that they have adequate resistances for peak forces. This process is carried out iteratively. For the earthquake records used, the proposed procedure leads to a design which achieves desired seismic behaviour, characterized by the stable elastic response of columns and braces, and with inelastic action confined primarily to links.<br>The procedure was implemented by means of three computer programs, two of which were developed as part of this study. The sensitivity of the procedure to initial section selection was studied and a methodology to obtain an appropriate site-specific earthquake record to use in the analysis was proposed.<br>The application of the procedure was illustrated through examples of three Chevron-type EBFs, these having four, eight and fourteen storeys and being located in Victoria, B.C. It was demonstrated that the proposed design method is simple and efficient, and can be used either as an alternative design method or in combination with current design practice. Analytical results indicate that frames designed using this alternative approach have improved behaviour compared to those designed in accordance with the present Canadian design requirements, in particular regarding the response of columns and braces.<br>In the second part of the study, the analytical tools developed were used to further investigate and enhance the understanding of seismic behaviour of EBFs. Modifications of seismic design requirements for EBFs, suitable for incorporation in the Canadian Standard for design of steel buildings, CSA/CAN-S16.1 were examined. The inelastic response of an eight-storey EBF designed following these modified requirements is compared to that of a corresponding structure designed using the iterative procedure. Attention was further directed to seismic force profiles, magnitudes of axial forces and moments for use in the design of columns, force modification factors and the relationship between inelastic inter-storey drifts and inelastic link deformations.
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Manafpour, Alireza. "Force and displacement-based seismic design of RC buildings." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398834.
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Redmond, Laura M. "Seismic performance, analysis, and design of hybrid concrete-masonry." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53497.
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Caribbean-style hybrid concrete-masonry structures consist of a reinforced concrete frame with partially grouted and reinforced infill masonry walls. The infill walls are typically connected to the RC frame with cast-in-place dowel reinforcement along one or more edges of the wall. There is limited guidance in masonry codes to design these types of structures, and their seismic performance has not been characterized with experimental tests. In this work, an experimental program characterized the seismic behavior of hybrid concrete-masonry frames and showed they do not exhibit the typical strut mechanism observed in unreinforced masonry infill structures. In addition, a detailed finite element modeling scheme and calibration methodology was developed for modeling partially grouted masonry. This model includes a novel calibration method to account for the difference in the shear and tensile behavior of bed joints with grouted and ungrouted cells, and a method to account for the contribution of vertical reinforcement to the shear capacity of the bed joints with grouted cells. Finally, simplified models were proposed for use in engineering design. A modification of the TMS 402 strut model for hybrid concrete-masonry was suggested to incorporate the effects of the masonry infill and connections in large models.
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Seymour, Douglas (Douglas Benjamin). "Design of innovative dynamic systems for seismic response mitigation." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/74497.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 97-99).<br>Rocking wall systems consist of shear walls, laterally connected to a building, that are moment-released in their strong plane. Their purpose is to mitigate seismic structural response by constraining a building primarily to a linear fundamental mode. This constraint prevents mid-story failure, and maximizes energy dissipation by activating the maximum number of plastic hinges throughout the structure. This is a useful response mitigation system, but suffers from some difficulties, stemming primarily from the considerable mass of the wall. Those difficulties are notably expensive foundations, and very high inertial forces imparted to the building, with subsequent need for expensive lateral connectors. The purposes of this work are to analyze current implementations of rocking wall systems, present an early reference on their application, present the first systematic methodology for their design, clarify their analysis, and introduce an alternative structural system that avoids their difficulties. A quasi-static analysis model is used for predicting the seismic mitigation performance of rocking walls and rocking columns. The stiffness matrix is generalized for an N-story building equipped with these structural systems. The model presented enables optimization of the design parameters, and consequently improved system effectiveness, analytical tractability, and material usage. The case study is a rocking wall system installed in a building located in Tokyo, Japan. A software package is developed, providing an illustrative implementation of the methods derived.<br>by Douglas Seymour.<br>S.M.
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Themelis, Spyridon. "Pushover analysis for seismic assessment and design of structures." Thesis, Heriot-Watt University, 2008. http://hdl.handle.net/10399/2170.
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The earthquake resistant design of structures requires that structures should sustain, safely, any ground motions of an intensity that might occur during their construction or in their normal use. However ground motions are unique in the effects they have on structural responses. The most accurate analysis procedure for structures subjected to strong ground motions is the time-history analysis. This analysis involves the integration of the equations of motion of a multi-degree-of-freedom system, MDOF, in the time domain using a stepwise solution in order to represent the actual response of a structure. This method is time-consuming though for application in all practical purposes. The necessity for faster methods that would ensure a reliable structural assessment or design of structures subjected to seismic loading led to the pushover analysis. Pushover analysis is based on the assumption that structures oscillate predominantly in the first mode or in the lower modes of vibration during a seismic event. This leads to a reduction of the multi-degree-of-freedom, MDOF system, to an equivalent single-degreeof- freedom, ESDOF system, with properties predicted by a nonlinear static analysis of the MDOF system. The ESDOF system is then subsequently subjected to a nonlinear timehistory analysis or to a response spectrum analysis with constant-ductility spectra, or damped spectra. The seismic demands calculated for the ESDOF system are transformed through modal relationships to the seismic demands of the MDOF system. In this study the applicability of the pushover method as an alternative mean to general design and assessment is examined. Initially a series of SDOF systems is subjected to two different pushover methods and to nonlinear-time-history analyses. The results from this study show that pushover analysis is not able to capture the seismic demands imposed by far-field or near-fault ground motions, especially for short-period systems for which it can lead to significant errors in the estimation of the seismic demands. In the case of near-fault ground motions the results suggest that pushover analysis may underestimate the displacement demands for systems with periods lower than half the dominant pulse period of the ground motion and overestimate them for systems with periods equal or higher than half the dominant pulse period of the ground motion. Subsequently a two-degree-offreedom, 2-DOF, is studied in the same manner with specific intention to assess the accuracy of the different load patterns proposed in the literature. For this system pushover analysis performed similarly as in the SDOF study. Finally the method is applied on a four-storey reinforced concrete frame structure. For this study pushover analysis was not effective in capturing the seismic demands imposed by both a far-field and a near-fault ground motion. Overall pushover analysis can be unconservative in estimating seismic demands of structures and it may lead to unsafe design.
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Whittle, Jessica Kaye. "Strategic placement of viscous dampers for seismic structural design." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:58ea0592-a6de-438d-bc8c-5cc3cf1cf9ea.
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Seismic design with viscous devices is an effective means of dissipating seismic energy and protecting the main structural system from permanent damage. Despite numerous damper placement methods available, there lacks consensus on the best method, thus leaving design engineers without recommended placement strategies. The purpose of this research is to investigate strategic placement of viscous dampers for seismic design and to offer design recommendations for placing dampers, vertically and horizontally. Five damper placement techniques were selected for investigation, including standard methods, Uniform and Stiffness Proportional damping, and advanced methods, the Simplified Sequential Search Algorithm (SSSA method), the Optimal Damper Placement for Minimum Transfer Functions (Takewaki method), and the Fully-stressed Analysis/Redesign method (Lavan A/R method). Effectiveness of the techniques for distributing linear fluid viscous dampers for two building examples was evaluated under a suite of twenty ground motions, two seismic hazard levels, and in terms of peak interstorey drifts, absolute accelerations, and residual drifts using nonlinear time history analysis. The advanced methods showed comparable performance based on performance indicators. Therefore, usability is recommended as the selection criteria. The Lavan A/R method was found to be the most effective and usable method. It is recommended that multiple design ground motions be used for the SSSA Mode and Lavan A/R methods as well as caution against removal of upper storey damping, which prompts susceptibility to larger roof drifts due to higher-mode effects. Various brace-damper arrangements were explored to determine strategic horizontal damper placement. It was found that brace-damper arrangements with diagonals and multiple brace- damper sets per floor pose effective means of distributing the axial damper force and protecting the lower-storey columns from overstressing. Behavioural testing of two nonlinear viscous devices was performed, and results were used to determine analytical models for the nonlinear fluid viscous and fluid spring devices based on fitted parameters. It was found that the stress-relaxation models better captured the nonlinearity of the devices than standard models but yielded only marginally decreased energy dissipation per cycle. Thus, it is recommended that standard models are adequate for analysis of damped structures with these nonlinear viscous devices.
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Malushte, Sanjeev R. "Prediction of seismic design response spectra using ground characteristics." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45802.
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<p>The available earthquake records are classified into five groups according to their
site stiffness and epicentral distance as the grouping parameters. For the groups
thus defined, normalized response spectra are obtained for single-degree-ofâ freedom
and massless oscillators. The effectiveness of the grouping scheme is examined by
studying the variance of response quantities within each group. The implicit
parameters of average frequency and significant duration are obtained for each group
and their effect on the response spectra is studied. Correlation analyses between
various ground motion characteristics such as peak displacement, velocity,
acceleration and root mean square acceleration are carried out for each group.</p>
<p>Smoothed design spectra for relative and pseudo velocities and relative
acceleration responses of single degree of freedom oscillators and the velocity and
acceleration responses of massless oscillators are proposed for each group.
Methods to predict relative velocity and relative acceleration spectra directly from the
pseudo velocity spectra are presented. It is shown that the relative spectra can be
reliably estimated from the pseudo spectra. The site dependent design spectra are
defined for a wide range of oscillator periods and damping ratios.</p><br>Master of Science
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Liu, Qin Carleton University Dissertation Engineering Civil and Environmental. "A Study of seismic design spectra for highway bridges." Ottawa, 1997.
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Meng, Ronald L. "Design of moment end-plate connections for seismic loading." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-11082006-133629/.
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Zou, Xiaokang. "Optimal seismic performance-based design of reinforced concrete buildings /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202002%20ZOU.
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