Dissertations / Theses: 'Pushover analysis'

1

Alici, Firat Soner. "Generalized Pushover Analysis." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614434/index.pdf.

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Nonlinear response history analysis is considered as the most accurate analytical tool for estimating seismic response. However, there are several shortcomings in the application of nonlinear response history analysis, resulting from its complexity. Accordingly, simpler approximate nonlinear analysis procedures are preferred in practice. These procedures are called nonlinear static analysis or pushover analysis in general. The recently developed Generalized Pushover Analysis (GPA) is one of them. In this thesis study, GPA is presented and evaluated comparatively with the nonlinear time history analysis and modal pushover analysis. A generalized pushover analysis procedure was developed for estimating the inelastic seismic response of structures under earthquake ground excitations (Sucuoglu and Gü
nay, 2011). In this procedure, different load vectors are applied separately to the structure in the incremental form until the predefined seismic demand is obtained for each force vector. These force vectors are named as generalized force vectors. A generalized force vector is a combination of modal forces, and simulates the instantaneous force distribution on the system when a given response parameter reaches its maximum value during the dynamic response. In this method, the maximum interstory drift parameters are selected as target demand parameters and used for the derivation of generalized force vectors. The maximum value of any other response parameter is then obtained from the analysis results of each generalized force vector. In this way, this procedure does do not suffer from the statistical combination of inelastic modal responses. It is further shown in this study that the results obtained by using the mean spectrum of a set of ground motions are almost identical to the mean of the results obtained from separate generalized pushover analyses under each ground motion in the set. These results are also very close to the mean results of nonlinear response history analyses. A practical implementation of the proposed generalized pushover analysis is also developed in this thesis study where the number of pushovers is reduced in view of the number of significant modes contributing to seismic response. It has been demonstrated that the reduced generalized pushover analysis is equally successful in estimating maximum member deformations and member forces as the full GPA under a ground excitation, and sufficiently accurate with reference to nonlinear response history analysis.

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2

Kaatsiz, Kaan. "Generalized Pushover Analysis For Unsymmetrical-plan Buildings." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614482/index.pdf.

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Nonlinear response history analysis is regarded as the most accurate analysis procedure for estimating seismic response. Approximate analysis procedures are also available for the determination of seismic response and they are preferred over nonlinear response history analysis since much less computational effort is required and good response prediction is achieved by employing rather simple concepts. A generalized pushover analysis procedure is developed in this thesis study as an approximate analysis tool for estimating the inelastic seismic response of structures under earthquake ground excitations. The procedure consists of applying generalized force vectors to the structure in an incremental form until a prescribed target interstory drift demand is achieved. Corresponding generalized force vectors are derived according to this target drift parameter and include the contribution of all modes. Unlike many approximate analysis procedures, response of the structure is directly obtained from generalized pushover analysis results without employing a modal combination rule, eliminating the errors cultivating from these methods. Compared to nonlinear response history analysis, generalized pushover analysis is less demanding in computational effort and its implementation is simpler relative to other approximate analysis procedures. It is observed that the proposed analysis procedure yields results accurately in comparison to the other nonlinear pushover analysis methods. Accordingly it can be suggested as a convenient and sound analysis tool.

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3

Zheng, Ming M. Eng Massachusetts Institute of Technology. "Modal pushover analysis for high-rise buildings." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82829.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 50).
Pushover analysis is a nonlinear static analysis tool widely used in practice to predict and evaluate seismic performance of structures. Since only the fundamental mode is considered and the inelastic theorem is imperfect for the conventional pushover analysis, a modified Modal Pushover Analysis (MPA) is proposed by researchers. In this thesis, the theories of dynamics for single-degree-of-freedom (SDOF) and multiple-degree-of-freedom (MDOF) are introduced, including elastic analysis and inelastic analysis. The procedures and equations for time history analysis, modal analysis, pushover analysis and modal pushover analysis are discussed in detail. Then an 8-story height model and a 16-story height model are established for analysis. The pushover analysis is conducted for each equivalent SDOF system, and by combination of the distribution of 1 mode, 2 modes and 3 modes, the responses of modal pushover analysis are obtained. The results of pushover analysis and modal pushover analysis are compared with those of time history analysis. The results of the analysis show that the conventional pushover analysis is mostly limited to low- and medium-rise structures in which only the first mode is considered and where the mode shape is constant. The modal pushover analysis is shown to have a superior accuracy in evaluation of seismic demands for higher buildings, especially for story drift ratios and column shears. With this in mind, some design recommendations and areas of future work are proposed in the conclusion.
by Ming Zheng.
M.Eng.

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4

Oguz, Sermin. "Evaluation Of Pushover Analysis Procedures For Frame Structures." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606047/index.pdf.

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Pushover analysis involves certain approximations and simplifications that some amount of variation is always expected to exist in seismic demand prediction of pushover analysis. In literature, some improved pushover procedures have been proposed to overcome the certain limitations of traditional pushover procedures. The effects and the accuracy of invariant lateral load patterns utilised in pushover analysis to predict the behavior imposed on the structure due to randomly selected individual ground motions causing elastic and various levels of nonlinear response were evaluated in this study. For this purpose, pushover analyses using various invariant lateral load patterns and Modal Pushover Analysis were performed on reinforced concrete and steel moment resisting frames covering a broad range of fundamental periods. Certain response parameters predicted by each pushover procedure were compared with the '
exact'
results obtained from nonlinear dynamic analysis. The primary observations from the study showed that the accuracy of the pushover results depends strongly on the load path, properties of the structure and the characteristics of the ground motion. Pushover analyses were performed by both DRAIN-2DX and SAP2000. Similar pushover results were obtained from the two different softwares employed in the study provided that similar approach is used in modeling the nonlinear properties of members as well as their structural features. The accuracy of approximate procedures utilised to estimate target displacement was also studied on frame structures. The accuracy of the predictions was observed to depend on the approximations involved in the theory of the procedures, structural properties and ground motion characteristics.

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5

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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6

Sapkota, Suman. "Seismic Capacity Evaluation of Reinforced Concrete Buildings Using Pushover Analysis." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544707728674621.

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7

Kadas, Koray. "Influence Of Idealized Pushover Curves On Seismic Response." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/3/12607761/index.pdf.

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Contemporary approach performance based engineering generally relies on the approximate procedures that are based on the use of capacity curve derived from pushover analysis. The most important parameter in the displacement-based approach is the inelastic displacement demand computed under a given seismic effect and the most common procedures employed for this estimation
the Capacity Spectrum Method and the Displacement Coefficient Method are based on bi-linearization of the capacity curve. Although there are some recommendations for this approximation, there is a vital need for rational guidelines towards the selection of the most appropriate method among several alternatives. A comprehensive research has been undertaken to evaluate the influence of several existing alternatives used for approximating the capacity curve on seismic demands. A number of frames were analyzed under a set of 100 ground motions employing OpenSees. In addition, the pushover curves obtained from nonlinear static analyses were approximated using several alternatives and the resulting curves were assigned as the force-deformation relationships of corresponding equivalent single-degree-of-freedom systems. These simplified systems were later analyzed to compute the approximate seismic response parameters. Using the results of the complex and simplified analyses, the performance of each approximation method was evaluated in estimating the &
#8216
exact&
#8217
inelastic deformations of the multi-degree-of-freedom systems at various degrees of inelasticity. Dependency of the errors on ductility, strength reduction factor and period was also investigated. The interpretations made and the conclusions drawn in this study is believed to clarify the rationality and accuracy of selecting the appropriate idealization of the capacity curve.

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8

Satyarno, Iman. "Adaptive pushover analysis for the seismic assessment of older reinforced concrete buildings." Thesis, University of Canterbury. Department of Civil Engineering, 2000. http://hdl.handle.net/10092/2882.

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It has been observed in major recent earthquakes that older reinforced concrete buildings experienced more serious damage than newer buildings. This is because they often present many structural deficiencies. To prevent further losses in future earthquakes, the seismic capacity of these older buildings needs to be assessed so that appropriate measures can be implemented to mitigate their vulnerability. In this research an adaptive pushover analysis is proposed as an analytical tool to carry out the seismic assessment of these older reinforced concrete buildings, where the following new methods and procedures are proposed. 1) A compound-spring member is used to model the critical regions in the members. This model accounts for possible failure in flexure, shear, or combined shear-flexure and makes the member's stiffness strength dependent. 2) The modified Rayleigh method is used to determine the lateral forces distribution and increment. 3) An automatic calculation of the structure's ductility is used for the seismic assessment using a force-based method. 4) Automatic calculations of the structure's lateral displacement capacity and effective period are used for the seismic assessment using a displacement based-method. 5) An automatic determination of the structural critical condition. 6) Step-by-step procedure to carry out a seismic assessment using the proposed adaptive pushover analysis. 7) The development of a pre-processor program to overcome difficulties in preparing the input data to carry out the analyses. The term adaptive is used because in each step of the analysis the following parameters are updated and evaluated as the lateral displacement is increased: 2000 11 1) flexural strength in the flexural spring, 2) shear strength in the shear spring, 3) lateral forces distribution and increment, 4) structural lateral strength, 5) structural period, 6) structural lateral displacement, 7) structural ductility. Using the proposed methods and the pre-processor program, the adaptive pushover analysis can directly give the following seismic capacity parameters using data obtained from the site or structural drawings. 1) Fundamental period, T₁ 2) Base shear capacity, Vbase 3) Effective period, Teff 4) Structure's ductility capacity, μ 5) Structure's lateral displacement capacity, δu Based on these parameters, the seismic assessment can then be carried out using either a forcebased method or a displacement-based method as suggested by NZNSEE (1996), where the seismic demand is determined from response spectra. In the force-based method the building is expected to perform satisfactorily during the seismic event corresponding to the given response spectra if the ductility capacity is greater than the ductility demand. In the displacement-based method the building is expected to perform satisfactorily during the seismic event corresponding to the given response spectra if the lateral displacement capacity is greater than the lateral displacement demand. If the seismic capacity is less than the seismic demand, a further step is then carried out to estimate the reliable earthquake return period in which the structure will perform satisfactorily so that decision on appropriate action can be made.

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9

Cavallari, Giulia. "Pushover analysis of an existing reinforced concrete bridge:Jamboree Road Overcrossing in Irvine, California." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3300/.

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The work for the present thesis started in California, during my semester as an exchange student overseas. California is known worldwide for its seismicity and its effort in the earthquake engineering research field. For this reason, I immediately found interesting the Structural Dynamics Professor, Maria Q. Feng's proposal, to work on a pushover analysis of the existing Jamboree Road Overcrossing bridge. Concrete is a popular building material in California, and for the most part, it serves its functions well. However, concrete is inherently brittle and performs poorly during earthquakes if not reinforced properly. The San Fernando Earthquake of 1971 dramatically demonstrated this characteristic. Shortly thereafter, code writers revised the design provisions for new concrete buildings so to provide adequate ductility to resist strong ground shaking. There remain, nonetheless, millions of square feet of non-ductile concrete buildings in California. The purpose of this work is to perform a Pushover Analysis and compare the results with those of a Nonlinear Time-History Analysis of an existing bridge, located in Southern California. The analyses have been executed through the software OpenSees, the Open System for Earthquake Engineering Simulation. The bridge Jamboree Road Overcrossing is classified as a Standard Ordinary Bridge. In fact, the JRO is a typical three-span continuous cast-in-place prestressed post-tension box-girder. The total length of the bridge is 366 ft., and the height of the two bents are respectively 26,41 ft. and 28,41 ft.. Both the Pushover Analysis and the Nonlinear Time-History Analysis require the use of a model that takes into account for the nonlinearities of the system. In fact, in order to execute nonlinear analyses of highway bridges it is essential to incorporate an accurate model of the material behavior. It has been observed that, after the occurrence of destructive earthquakes, one of the most damaged elements on highway bridges is a column. To evaluate the performance of bridge columns during seismic events an adequate model of the column must be incorporated. Part of the work of the present thesis is, in fact, dedicated to the modeling of bents. Different types of nonlinear element have been studied and modeled, with emphasis on the plasticity zone length determination and location. Furthermore, different models for concrete and steel materials have been considered, and the selection of the parameters that define the constitutive laws of the different materials have been accurate. The work is structured into four chapters, to follow a brief overview of the content. The first chapter introduces the concepts related to capacity design, as the actual philosophy of seismic design. Furthermore, nonlinear analyses both static, pushover, and dynamic, time-history, are presented. The final paragraph concludes with a short description on how to determine the seismic demand at a specific site, according to the latest design criteria in California. The second chapter deals with the formulation of force-based finite elements and the issues regarding the objectivity of the response in nonlinear field. Both concentrated and distributed plasticity elements are discussed into detail. The third chapter presents the existing structure, the software used OpenSees, and the modeling assumptions and issues. The creation of the nonlinear model represents a central part in this work. Nonlinear material constitutive laws, for concrete and reinforcing steel, are discussed into detail; as well as the different scenarios employed in the columns modeling. Finally, the results of the pushover analysis are presented in chapter four. Capacity curves are examined for the different model scenarios used, and failure modes of concrete and steel are discussed. Capacity curve is converted into capacity spectrum and intersected with the design spectrum. In the last paragraph, the results of nonlinear time-history analyses are compared to those of pushover analysis.

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10

Degirmenci, Can. "Dynamic Pull Analysis For Estimating The Seismic Response." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607833/index.pdf.

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The analysis procedures employed in earthquake engineering can be classified as linear static, linear dynamic, nonlinear static and nonlinear dynamic. Linear procedures are usually referred to as force controlled and require less analysis time and less computational effort. On the other hand, nonlinear procedures are referred to as deformation controlled and they are more reliable in characterizing the seismic performance of buildings. However, there is still a great deal of unknowns for nonlinear procedures, especially in modelling the reinforced concrete structures. Turkey ranks high among all countries that have suffered losses of life and property due to earthquakes over many centuries. These casualties indicate that, most regions of the country are under seismic risk of strong ground motion. In addition to this phenomenon, recent studies have demonstrated that near fault ground motions are more destructive than far-fault ones on structures and these effects can not be captured effectively by recent nonlinear static procedures. The main objective of this study is developing a simple nonlinear dynamic analysis procedure which is named as &ldquo
Dynamic Pull Analysis&rdquo
for estimating the seismic response of multi degree of freedom (MDOF) systems. The method is tested on a six-story reinforced concrete frame and a twelve-story reinforced concrete frame that are designed according to the regulations of TS-500 (2000) and TEC (1997).

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11

Leung, Colin. "SENSITIVITY OF SEISMIC RESPONSE OF A 12 STORY REINFORCED CONCRETE BUILDING TO VARYING MATERIAL PROPERTIES." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/681.

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The main objective of this investigation is to examine how various material properties, governed by code specification, affect the seismic response of a twelve- story reinforced concrete building. This study incorporates the pushover and response history analysis to examine how varying steel yield strength (Fy), 28 day nominal compressive concrete strength (f’c), modes, and ground motions may affect the base shear capacity and displacements of a reinforced concrete structure. Different steel and concrete strengths were found to have minimal impact on the initial stiffness of the structure. However, during the post-yielding phase, higher steel and concrete compressive strengths resulted in larger base shear capacities of up to 22%. The base shear capacity geometric median increased as f’c or Fy increased, and the base shear capacity dispersion measure decreased as f’c or Fy increased. Higher mode results were neglected in this study due to non-convergent pushover analyses results. According to the response history analysis, larger yield and concrete compressive strengths result in lower roof displacement. The difference in roof displacement was less than 12% throughout. This displays the robustness of both analysis methods because material properties have insignificant impact on seismic response. Therefore, acceptable yield and compressive strengths governed by seismic code will result in acceptable building performance.

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12

Gunay, Mehmet Selim. "An Equivalent Linearization Procedure For Seismic Response Prediction Of Mdof Systems." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609447/index.pdf.

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Nonlinear response history analysis is accepted as the most accurate analytical tool for seismic response determination. However, accurate estimation of displacement responses using conceptually simple, approximate analysis procedures is preferable, since there are shortcomings in the application of nonlinear response history analysis resulting from its complexity. An equivalent linearization procedure, which utilizes the familiar response spectrum analysis as the analysis tool and benefits from the capacity principles, is developed in this thesis study as an approximate method for predicting the inelastic seismic displacement response of MDOF systems under earthquake excitations. The procedure mainly consists of the construction of an equivalent linear system by reducing the stiffness of structural members which are expected to respond in the inelastic range. Different from similar studies in literature, equivalent damping is not explicitly employed in this study. Instead, predetermined spectral displacement demands are utilized in each mode of the equivalent linear system for the determination of global displacement demands. Response predictions of the equivalent linearization procedure are comparatively evaluated by using the benchmark nonlinear response history analysis results and other approximate methods including conventional pushover analysis and modal pushover analysis (MPA). It is observed that the proposed procedure results in similar accuracy with approximate methods which employ nonlinear analysis. Considering the conceptual simplicity of the procedure and the conventional analysis tools used in its application, presented equivalent linearization procedure can be suggested as a practically applicable method for the prediction of inelastic seismic displacement response parameters with sufficient accuracy.

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13

Chaulagain, Hemchandra. "Assessment of response reduction factor of RC buildings in Kathmandu Valley using non-linear pushover analysis." Master's thesis, Purbanchal University, 2010. http://hdl.handle.net/10773/12681.

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Master of Engineering in Earthquake
This study addresses the issue of response reduction factor which is used in modern codes to scale down the elastic response of the structure. The level of ductility and overstrength of RC buildings in Kathmandu valley are investigated. The ductility and overstrength factors are estimated by analyzing the buildings using non-linear pushover analysis for 12 engineered designed RC buildings of various characteristics representing a wide range of RC buildings in Kathmandu valley. Finally, the response reduction factor of RC building in Kathmandu valley is evaluated by using the relation of ductility and overstrength factor.

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14

Fang, Chia-hung. "The Seismic Behavior of Steel Structures with Semi-Rigid Diaphragms." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/75235.

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This thesis investigates the torsional performance of steel structures with and without rigid diaphragm constraints through numerical simulations and evaluates the appropriateness of relevant design provisions in current seismic design codes. In the first part of the work, six theme structures with different (1) in-plane stiffness of diaphragm, and (2) horizontal configurations of vertical braced frames were designed and their performance evaluated through both nonlinear static and dynamic analyses. Comparisons of the analytical results between the structures with and without rigid diaphragm constraints indicate that the in-plane rigidity of the diaphragms affects the efficiency of in-plane force transfer mechanisms, resulting in different global ductility and strength demands. Rigid diaphragm structures exhibit higher global strengths as well as higher torsional rotation capacity because of the infinite in-plane stiffness of the diaphragm. Semi-rigid diaphragm structures have higher ductility demands due to the finite in-plane diaphragm stiffness. The inclusion of bi-axial forces in the analyses reduces the structural strength and increases the ductility demands on the peripheral frames. The axial forces in the collectors and chords that make up the diaphragm depend on (1) the sequence of brace buckling and (2) vertical configuration of the braced frames. The results show higher axial forces in collectors in the roof diaphragms, and higher chord axial forces in the third floor diaphragms. The shear connections in the beams that make up both the collectors and chords are susceptible to failure due to the significant increment of axial forces in those members. The conventional beam analogy used in design can severely underestimate the axial forces in chords and collectors when the structures step into the inelastic stage.
Ph. D.

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15

Hughes, Douglas Grant Ramey G. Ed. "Bridge pile bent P-delta curves in transverse direction using FB-pier and GTSTRUDL pushover Analysis procedures." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Summer/master's/HUGHES_DOUGLAS_56.pdf.

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16

Faralli, Anna Chiara. "Seismic vulnerability of the ancient albergotti's manor in Arezzo, Italy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5956/.

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The thesis moves from the need of understanding how a historical building would behave in case of earthquake and this purpose is strongly linked to the fact that the majority of Italian structures are old ones placed in seismic sites. Primarily an architectural and chronological research is provided in order to figure out how the building has developed in time; then, after the reconstruction of the skeleton of the analyzed element (“Villa i Bossi” in Gragnone, AR), a virtual model is created such that the main walls and sections are tested according to the magnitude of expected seismic events within the reference area. This approach is basically aimed at verifying the structure’s reliability as composed by single units; the latter are treated individually in order to find out all the main critical points where rehabilitation might be needed. Finally the most harmful sections are studied in detail and proper strengthening is advised according to the current know-how.

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17

Marino, Salvatore. "Mechanical behaviour of composite spandrels in unreinforced masonry buildings." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5951/.

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La presente tesi tratta il comportamento meccanico delle fasce di piano in muratura composite. Con tale termine ci si riferisce alle fasce di piano che hanno al di sotto un elemento portante in conglomerato cementizio armato, come ad esempio cordoli o solai. Assieme ai maschi murari, le fasce di piano costituiscono gli elementi portanti di una parete in muratura. Tuttavia, in caso di analisi sismica di un edificio in muratura, l’effetto fornito da tali elementi è trascurato e si considera solamente il contributo dei maschi murari. Ciò è dovuto anche alla scarsa conoscenza che ancora oggi si possiede sul loro comportamento meccanico. Per questo motivo diversi gruppi di ricerca tutt’ora sono impegnati in tale studio. In particolare, il lavoro di questa tesi, s’inserisce nel più ampio progetto di ricerca condotto dalla professoressa Katrin Beyer, direttrice del Laboratorio di Ingegneria Sismica e Dinamica Strutturale del Politecnico di Losanna (Svizzera).

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18

Fernández, López Rodrigo Miguel, and Velásquez Ricardo Timoteo Zapata. "Análisis y diseño estructural de una torre de 40 pisos y 4 sótanos siguiendo normas peruanas incluyendo su desempeño sísmico en el distrito de Santiago de Surco, Lima." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652425.

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En la presente investigación se realizará el análisis y diseño estructural de una torre de 40 pisos y 4 sótanos de concreto armado siguiendo normas peruanas y el cálculo de desempeño sísmico en el distrito de Santiago de Surco, Lima. Para esto, la hipótesis plantea sí las normas peruanas cumplen con el desempeño sismorresistente deseado para una torre alta como esta. Para un entendimiento progresivo, primero se hará una descripción de la torre alta a estudiar, su arquitectura, estructura, suelo y otros. En la segunda parte se darán los conceptos necesarios para comprender los tipos de análisis lineal estático, lineal dinámico y no lineal estático. Se definirán los materiales, los diagramas momento – rotación también se explicará la obtención de la curva de capacidad del edificio. Se tocarán conceptos de viento y nivel de desempeño. En la tercera parte, se procederá con en análisis sísmico cumpliendo las exigencias de sismorresistencia, también se hará el análisis por viento para comparar ambos efectos. En el capítulo cuarto se procederá a hacer el diseño estructural usando las normas de concreto armado. En el capítulo cinco se hará el análisis por desempeño usando el método pushover para finalmente conseguir los resultados de este proyecto y a las conclusiones de este desarrollo.
In the present investigation, the analysis and structural design of a 40-storey tower and 4 reinforced concrete basements will be carried out following Peruvian regulations and the calculation of seismic performance in the Santiago de Surco district, Lima. For this, the hypothesis states whether the Peruvian standards meet the desired seismic resistance performance for a tall tower like this one. For a progressive understanding, first a description will be made of the tall tower to study, its architecture, structure, soil and others. In the second part, the concepts necessary to understand the types of static linear analysis, dynamic linear analysis and static non-linear analysis will be given. The materials will be defined, the moment - rotation diagrams will also explain the obtaining of the building capacity curve. Wind and performance level concepts will be discussed. In the third part, we will proceed with seismic analysis complying with the seismic resistance requirements, we will also do the wind analysis to compare both effects. In the fourth chapter, the structural design will be carried out using the reinforced concrete standards. In chapter five the performance analysis will be done using the pushover method to finally get the results of this project and the conclusions of this development.
Tesis

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19

Alamri, Amro Abdullah. "DEVELOPING A FULL THREE-DIMENSIONAL MODEL OF SELF-CENTERING CONCENTRICALLY BRACED FRAME SYSTEMS USING NONLINEAR STATIC PUSHOVER ANALYSIS." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1627680240922479.

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20

Tsai, Pin-Hui. "Seismic evaluation of traditional timber structures in Taiwan." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503662.

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Taiwan is located in a highly seismic zone and the historical “Dieh-Dou” timber buildings, constructed without following any code or standard, are prone to collapse under earthquake. These buildings are unique and represent the culture, heritage and art of Taiwan, therefore need to be preserved while minimizing unnecessary intervention that could damage their authenticity.
This research comprises a thorough investigation on the parameters influencing the seismic vulnerability of the Dieh-Dou timber frames in Taiwan, and propose a methodology of assessment and a strategy for strengthening validated through experimental testing and numerical analysis.
After review existing literature and post-earthquake surveys, the failure modes of the buildings are identified, showing that the dislocation of the elements of the frame from the joints is the primary source of damage. An experimental investigation is carried out comprising both rotational and translational tests on full scale joint specimens which, together with a parametric study undertaken with an appropriate FE simulation, demonstrates how both the rotational and translational stiffness of the joints play a key role in defining the behaviour of these structures.
Lateral force, response spectrum, and step-by-step pushover analyses are performed and compared with the post-earthquake survey of two Dieh-Dou buildings seriously affected by the 1999 Chi-Chi earthquake. The results show that the proposed FE modelling can successfully be employed to assess the vulnerability of the frames.
Based on a damage level approach, an assessment methodology is suggested that would allow to optimisation of the strengthening strategy, permitting protection these precious structures from future earthquakes while avoiding unnecessary interventions.

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21

Oksuz, Arif. "Software Development For R/c Building Vulnerability Index And Member Importance Calculation." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12604847/index.pdf.

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SOFTWARE DEVELOPMENT FOR R/C BUILDING VULNERABILITY INDEX AND MEMBER IMPORTANCE CALCULATION Turkey has many active faults which have the potential to generate large earthquakes. Recent earthquakes showed that the buildings in Turkey are not well designed and vulnerable to earthquakes. Previous studies on the subject showed that many structures in Turkey need to be strengthened before the next major earthquake to minimize property loss and casualties. A number of fast and approximate (mostly empirical) methods have been developed in the past to process large building stock. However, there are some important and special structures that do not fit with the general building stock and needs special consideration (e.g., disaster management center, governmental buildings, hospitals, tall structures, etc.). This study targets to evaluate those important and special structures in a detailed, fast, and correct manner. The developed software, which constitutes an important part of this study, does process the building information several times to determine member-based importance factors. The vulnerability index of the building will be determined using the importance of each load-carrying member and how much each member is forced with respect to its capacity. In order to augment user perception, a functional graphical user-interface is designed. Software is equipped with modules that generate input files for SAP2000 analysis program, conduct dynamic and static analysis automatically, and postprocess the generated analysis results which enable the engineer to make a decision on the vulnerability of the structure. Program is written in C++, using object-oriented programming technique. The main difference between this and similar studies is the generator program which automatically generates 3D-FE models and post-processes nonlinear analysis results for an effective decision mechanism. In this way, more realistic results can be obtained much faster. As future studies, new routines are planned to be implemented to the graphical user interface of the program which will suggest smart and engineered retrofit/strengthening alternatives to the user.

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22

Estrella, Chavez Juan Jacob, and Zamalloa Ángel Jair Ochoa. "Determinación de la vulnerabilidad sísmica del Mercado Municipal del Balneario de Pucusana mediante el análisis estático no lineal “pushover”." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/657564.

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Debido al alto peligro de ocurrencia de sismo, al que está expuesto el balneario de Pucusana y el crecimiento poblacional que ha tenido en los últimos años, hace necesario conocer los efectos que producirían un sismo de gran magnitud en esta localidad, según (Silgado, 1978), en el año 1746 ocurrió un sismo de magnitud estimada de 9.0 MW, seguido de un maremoto que destruyó el puerto del callao y según (Tavera, 2008), el área de estudio ocupa una zona de peligro estimado, se espera un sismo de magnitud 8.8 MW, producto de estos estudios se consideró escoger esta localidad como representativa para elaborar un escenario de riesgo sísmico. Ante esta realidad, se hace necesario elaborar escenarios de Riesgo para el balneario de Pucusana. Este trabajo de investigación pretende realizar una mejora a la propuesta realizada por el CENEPRED, en su manual de estimación del riesgo, utilizando el Análisis “PUSHOVER”, mediante la metodología ATC-40, el ASCE41-13 y SEAOC VISION 2000, que permitirá determinar la calidad de la estructura a detalle y compararla con el nivel de peligro de sismo que se tiene producto de los trabajos del proyecto SIRAD 2012. Se ha escogido para realizar este estudio el Mercado Municipal, debido a que es una de las estructuras más importantes del Balneario. Finalmente, el aporte de esta tesis es determinar el nivel de desempeño del mercado municipal de Pucusana, para la determinación del nivel de vulnerabilidad del mismo.
Due to the high danger of earthquake occurrence, to which the Pucusana city is exposed and the population growth that it has had in recent years, it is necessary to know the effects that a large earthquake would produce in this locality, according to (Silgado, 1978 ), in the year 1746 an earthquake of estimated magnitude of 9.0 MW occurred, followed by a tsunami that destroyed the port of Callao and according to (Tavera, 2008), the study area occupies an estimated danger zone, an earthquake of magnitude 8.8 MW, as a result of these studies, it is considered to choose this locality as representative to elaborate a seismic risk scenario. Given this reality, it is necessary to develop Risk scenarios for the Pucusana spa. This research work aims to make an improvement to the proposal made by CENEPRED, in its risk estimation manual, using the “PUSHOVER” Analysis, using the ATC-40 methodology, ASCE41-13 and SEAOC VISION 2000, which will determine the quality of the structure in detail and compare it with the level of earthquake danger that exists as a result of the work of the SIRAD 2012 project. The Municipal Market has been chosen to carry out this study, because it is one of the most important structures in the Spa. Finally, the contribution of this thesis is to determine the level of performance of the municipal market of Pucusana, to determine its level of vulnerability.
Tesis

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23

Maddala, Padmakar. "Pushover Analysis of Steel Frames." Thesis, 2013. http://ethesis.nitrkl.ac.in/5347/1/211CE2236.pdf.

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In last decades Steel structure has played an important role in construction Industry. It is necessary to design a structure to perform well under seismic loads. The seismic performance of a multi-story steel frame building is designed according to the provisions of the current Indian code (IS 800 -2007). The shear capacity of the structure can be increased by introducing Steel bracings in the structural system. Bracings can be used as retrofit as well. There are „n‟ numbers of possibilities to arrange Steel bracings such as D, K, and V type eccentric bracings. A typical six-story steel frame building is designed for various types of eccentric bracings as per the IS 800- 2007. D, K, and V are the different types of eccentric bracings considered for the present study. Performance of each frame is studied through nonlinear static analysis.

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24

SINGH, REKHA. "PUSHOVER ANALYSIS OF MULTISTOREY BUILDING." Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14387.

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ABSTRACT In the practical design applications the evaluation of seismic response is usually based on linear elastic structural behaviour. However this approach may be not sufficient in limiting the damage levels of the buildings. To this purpose more accurate methods of analyses, which can predict the real behaviour under strong seismic actions, are required. The non-linear dynamic analysis is the most rigorous method. The non-linear static pushover analysis seems to be a more rational method for estimating the lateral strength and the distribution of inelastic deformations. In this thesis Pushover analyses were performed by ETABS to predict the behaviour under strong seismic action and comparing the forces in static linear and nonlinear analysis.

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25

Xie, Bing-kun, and 謝秉坤. "Frame Model of Nonlinear Pushover Analysis." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/98je74.

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碩士
國立交通大學
土木工程系所
101
This research simulates the reinforced concrete frame in different nonlinear analysis method, and reorganizes the flow and the application pushover analysis method; first, to consider the reinforced concrete material nonlinear, cuts the round number element by to analyze the cross section; second, to calculate the reinforced concrete cross section bending moment and curvature nonlinear relationship, and carries on the frame analysis using the bending moment and curvature, finally first carries on the nonlinear pushover analysis the reinforced concrete column, to simulate the centralized spring bending moment and corner behavioral analysis way simulation using the capacity diagram of curves definition. This research by establishes the nonlinear analysis program and national center for research on earthquake engineering the simulation plastic hinge pattern carries on the portal frame the nonlinear pushover analysis, and discussed the difference. Finally carries on big frame case study, derives the centralized spring constant to analyze by pushover of analysis the nonlinear material, capacity of diagram of curves and bending moment displacement relational graph the results analysis will carry on the contrast judgment plastic hinge to have the position and order.

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26

Chou, Wen-hsiang, and 周文翔. "The Pushover Analysis for Irregular Structure." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/41693910745732123101.

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碩士
國立臺灣科技大學
營建工程系
98
Pushover analysis is a simple and convenient method to do the seismic evaluation of buildings. However, because there are many different types of structures thus pushover cannot reflect the actual behavior of the structures. From several major earthquakes, we found one of the main reason for the structural damage was due to irregular structures. So if we can further understand the pushover analysis for the behavior in irregular structures, it will facilitate development of pushover analysis. This research used the ETABS with NCREE for the development of reinforced concrete plastic hinges to observe and discuss the pushover analysis for the behavior of irregular structures by comparing different lateral forces and diaphragm assumptions to study the differences in the building performance. By analyzing the results, we can generalize the advantages, disadvantages, and the applicability for the pushover analysis for irregular structures for engineers to deal with similar cases in their design.

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27

Lai, Zhi-Yu, and 賴志瑜. "Behavior of Pushover Analysis of Frame." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/34971817222777419895.

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碩士
國立交通大學
土木工程學系
101
The study is to explore the fundamental mechanical behavior on pushover analysis of frame by using the finite element software OpenSees. Taking RC frames as examples subjected to lateral horizontal load, with the definition of plastic hinge as recommended by National Center for Research on Earthquake Engineering. Pushover analysis on OpenSees is proceed by considering the plastic hinge as zero in length of rotational spring and use of concentrated plasticity model. Model validation is by cantilever and 1x1 frame to conduct pushover analysis. Moreover, it is verified by basic mechanical formula and structural analysis and it can be seen as the value of reference with the results of the simulation on mechanical behavior of structural analysis. Finally, conduct the practical discussion on RC framework of beam-column joint of rigid zone through 1x1, 2x1, 2x8 frames and pushover analysis to compare with ETABS software packages. According to the results, it is consistent up to the ultimate point on OpenSees and ETABS; but over the ultimate point, OpenSees stopped and capacity curve from ETABS decreased.

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28

Sethy, Kaliprasanna. "Application of pushover analysis to RC bridges." Thesis, 2011. http://ethesis.nitrkl.ac.in/2833/1/209CE2046.pdf.

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After 2001 Gujarat Earthquake and 2005 Kashmir Earthquake, there is a nation-wide attention to the seismic vulnerability assessment of existing buildings. There are many literatures available on the seismic evaluation procedures of multi-storeyed buildings using nonlinear static (pushover) analysis. There is no much effort available in literature for seismic evaluation of existing bridges although bridge is a very important structure in any country. There are presently no comprehensive guidelines to assist the practicing structural engineer to evaluate existing bridges and suggest design and retrofit schemes. In order to address this problem, the aims of the present project was to carry out a seismic evaluation case study for an existing RC bridge using nonlinear static (pushover) analysis. Bridges extends horizontally with its two ends restrained and that makes the dynamic characteristics of bridges different from building. Modal analysis of a 3D bridge model reveals that it has many closely-spaced modes. Participating mass ratio for the higher modes is very high. Therefore, pushover analysis with single load pattern may not yield correct results for a bridge model. A 12-span existing RC bridge was selected for the case study. Standard pushover analysis using FEMA 356 (2000) displacement coefficient method and an improved upper bound pushover analysis method were used to analyse the building. Some of the analysis parameters were suitably modified to use in a bridge structure. The evaluation results presented here shows that the selected bridge does not have the capacity to meet any of the desired performance level.

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29

"EVALUATION OF PUSHOVER ANALYSIS PROCEDURES FOR FRAME STRUCTURES." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606047/index.pdf.

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30

Liao, Hao-Jen, and 廖晧荏. "Pushover Analysis and Seismic Assessment for Irregular Bridges." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/04448167703640484705.

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碩士
中原大學
土木工程研究所
99
Pushover analysis provides a simple process to study the nonlinear behavior of structures and has rapidly become popular for seismic assessment of bridges in recent years. However, pushover analyses which are originally developed for building structures have two inherent drawbacks in that it is restricted with a single mode response and the lateral force distribution during the pushover process is invariant. As such, the pushover analysis can be reliably applied only on the regular structures and it can not account for the force redistribution after structure yields. Several researchers in the past few years have proposed some improved methods to overcome this problem. Unfortunately, most of these refined methods were aimed at solving problems related to buildings, not to bridges. Due to the intrinsic difference of seismic responses between buildings and bridges, further clarification of the circumstances under which these improved methods can produce reliable estimates for bridges in the practice is needed. This research firstly attempts to specify quantitatively the scope of applicability for current pushover analyses on continuous irregular bridges. The effects of different load patterns of lateral forces and monitoring points on the seismic assessment are discussed. Secondly, a simplified modal pushover method is proposed to study the contributions of high modes of irregular bridges on the seismic assessment. Thirdly, a single-run procedure with fully adaptive and multi-modal considerations is developed. The numerical results from current pushover analyses are compared with those from adaptive pushover analyses. Finally, this research develops an in-house program, including modal and nonlinear analyses, to modify the drawbacks of current pushover analysis.

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HUA, HSIAO CHIUNG, and 蕭瓊華. "The Pushover Analysis Containg in Plane Brick Wall." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/64586074980194168183.

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碩士
大漢技術學院
土木工程與環境資源管理研究所
102
The seismic capacity estimate and retrofit by pushover analysis of low buildings in Taiwan. Pushover analysis is base on shear building theory and there have two methods SERCB and TEASPA. Most of low buildings analysis is using TEASPA. However, TEASPA in brick wall analysis suggest that using equivalent diagonal strut simulation to make brick wall as the independent member and limit aspect ratio between 0.5 and 2 that lead the analysis often underestimate the strength that can’t simulate the destroy between the column and brick wall. This study was including the contribution of brick wall and unlimited by aspect ratio in analysis, so we don’t use diagonal strut simulation brick wall additional to use the concept of same displacement to superposition the capacity curve of column and brick wing wall as a combine column and substitution the model of nonlinear hinge in original column by TEASPA. The post shear strength analysis obviously higher 30 % than TEASPA. The lateral displacement at post strength and development of nonlinear hinge are close to the result in-site static pushover test in Kou-Ho. Despite the suggestion of this study were more complex, it is still a viable way.

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32

Kuo, Chun-Wei, and 郭峻瑋. "Tests and Nonlinear Pushover Analysis of Water Pipeline." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/64554135043760333060.

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碩士
國立臺灣大學
土木工程學研究所
100
In this study, the major research direction divides into two parts. One is the tests of ductile iron water pipes with type K joints including axial tension, axial compression and four points bending tests. Another is the nonlinear pushover analysis of continuous ductile iron water pipeline under strike-slip fault. Ductile iron pipe, which is one of the commonly used water pipeline at Taiwan, has many advantages, such as high strength, ductility and economic and so on. The type K joint utilize rubber and pressing ring to reach high tightness of water and enough bending angle. In this study, three tests of water pipes with joints are carried out to get the relationship curves of tension-displacement, compression-displacement and moment-rotation. Before carrying out nonlinear pushover analysis of pipelines, nonlinear plastic hinges must be set. In the early literature, material parameter and the analysis of ABAQUS are used to set the axial and moment plastic hinges. In this study, we set the modified axial compression plastic hinges by combing the result of the tests with analysis of nonlinear compression models. Combing the results of the two parts, we investigate the verifications of pushover analysis under the strike-slip fault by considering allowable fault displacement and failure model of pipes. Under the failure mode controlled by compression and bending of the pipes, the allowable fault displacement tends to decrease. On the other hand, under the failure mode controlled by tension and bending of the pipes, the results of pushover analysis are similar to the early literature.

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33

Tripathy, Rasmita. "Pushover Analysis Of R/C Setback Bulding Frames." Thesis, 2012. http://ethesis.nitrkl.ac.in/4551/1/609CE302.pdf.

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The behaviour of a multi-storey framed building during strong earthquake motions depends on the distribution of mass, stiffness, and strength in both the horizontal and vertical planes of the building. In multi-storeyed framed buildings, damage from earthquake ground motion generally initiates at locations of structural weaknesses present in the lateral load resisting frames. Further, these weaknesses tend to accentuate and concentrate the structural damage through plastification that eventually leads to complete collapse. In some cases, these weaknesses may be created by discontinuities in stiffness, strength or mass between adjacent storeys. Such discontinuities between storeys are often associated with sudden variations in the frame geometry along the height. There are many examples of failure of buildings in past earthquakes due to such vertical discontinuities. Irregular configurations either in plan or elevation were often recognised as one of the main causes of failure during past earthquakes. A common type of vertical geometrical irregularity in building structures arises from abrupt reduction of the lateral dimension of the building at specific levels of the elevation. This building category is known as the setback building. Many investigations have been performed to understand the behaviour of irregular structures as well as setback structures and to ascertain method of improving their performance. Pushover analysis is a nonlinear static analysis used mainly for seismic evaluation of framed building. Conventional pushover analysis outlined in FEMA 356:2000 and ATC 40:1996 is limited for the buildings with regular geometry. It may not be possible to evaluate the seismic performance of setback building accurately using conventional nonlinear static (pushover)analysis outlined in FEMA 356:2000 and ATC 40:1996, because of its limitations for the irregular structures with significant higher modes effects. There is no research effort found in the literature to use this analysis procedure for setback building. It is instructive to study the performance of conventional pushover analysis methodology as well as other alternative pushover methodologies for setback buildings and to suggest improvements suitable for setback buildings. In the present study an improved procedure for estimating target displacement of setback buildings is proposed. This proposal is a simple modification of the displacement coefficient method as outlined in FEMA 356: 2000. A parametric study is also carried out to understand the applicability of existing lateral load patterns on the pushover analysis of setback building. It is found that mass proportional uniform load pattern is most suitable amongst others for pushover analysis of setback buildings. The results of the study show that pushover analysis carried out by mass proportional uniform load pattern and proposed modification in target displacement estimation procedure consistently predicting the results close to that of nonlinear dynamic analyses.

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34

SUMBRIA, ROHIT. "PUSHOVER ANALYSIS OF 7 STOREY BUILDING USING SAP2000." Thesis, 2018. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16278.

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Elastic method of analysis indicates elastic capacity of structures and tells us about location of first yielding but it cannot capture important phenomena’s that control seismic performance of structures during severe ground shaking. Thus, for design and evaluation of structures, inelastic procedures are being used by engineers to understand structural behaviour during earthquakes with the assumption that elastic capacity of structure will be exceeded. Pushover analysis includes pushing the structure using invariant load pattern to get force – deformation relationship. While performing the pushover analysis, it is assumed that structural response is dominated by the fundamental mode. Development of plastic hinges can be monitored during the analysis. In the present study, non-linear pushover analysis using SAP2000 using invariant loading pattern has been carried out with the intention to investigate the relative importance of several factors in the non-linear analysis of frames. Relevant codes (ATC 40, FEMA273, FEMA356 and FEMA440) have been referred.

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35

BANSAL, KUNAL. "PUSHOVER ANALYSIS OF 15 STOREY STEEL BUILDING USING SAP2000." Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/15214.

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To model the complex behavior of steel building analytically in its non-linear zone is difficult. This has led engineers in the past to rely heavily on empirical formulas, which were derived from numerous experiments for the design of steel structures. For structural design and assessment of steel members, the non-linear analysis has become an important tool. The method can be used to study the behavior of steel structures including force redistribution. This analysis of the nonlinear response of steel structures to be carried out in a routine fashion. It helps in the investigation of the behavior of the structure under different loading conditions, its load deflection behavior and the cracks pattern. In the present study, Pushover analysis to obtain nonlinear response of steel frame using SAP2000 under the specify loading as per given in code has been carried out with the intention to investigate the relative importance of several factors in the non-linear analysis of steel frames.

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36

LEE, HSIEN TING, and 李賢鼎. "Damage Assessment of Building with Nonlinear Static Pushover Analysis." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/26598163703941091982.

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碩士
中國科技大學
土木與防災應用科技研究所
94
This research is to conduct a damage assessment of a nine story of RC moment- resisting frame with Capacity Spectrum Method (CSM). A bare frame and a frame with RC shear walls are analyzed to highlight the effects of RC shear walls. The nonlinear behaviors of structural members are simulated with the concentrated plastic hinges. The columns are simulated with incorporating the confined effects at the plastic hinge zones at the ends of members to reflect the flexural hinges, where Meander’s formulation is adopted herein. The identical simulation is also implemented to the beam elements, but without taking into account of confined effects at the plastic hinges. RC shear walls are converted into equivalent columns in addition to flexural hinges at the ends of members, and at the mid-length of members specified with a shear hinge account for shear failure modes. The relations of moment-curvature at the plastic hinges are achieved with a fiber element formulation. The methodology in ATC 40 procedure is adopted to perform a nonlinear pushover analysis. Demanding spectra include a seismic design earthquake (PGA=0.24g) and a maximum credible earthquake (PGA=0.32g). Story drift ratios are served as a damage indicator with damage states stipulated in HAZUS99. Even slight in-plane torsion in this building, no significant deficiency appears on either the frames or the frames with shear walls.

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37

Tsai, Kun-Lung, and 蔡坤龍. "Establishment of Information Platform for Pushover Analysis of Building." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/pj336t.

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碩士
國立臺北科技大學
土木與防災研究所
99
This thesis aims at developing a framework, VISUAL_SERCB_2.0, to visualize the seismic evaluation result of the reinforced concrete (RC) building using the qualified program SERCB. All the information required for the evaluation including the cross sectional data, the detailed arrangement of reinforcement, the crack propagation and plastic hinge development of all the RC members such as beam, column and wall during different pushover process are able to be displayed graphically. Eventually, the failure process of the RC building can be demonstrated visually in sequence. The Visual C++ language associated with the OpenGL library serves as the core of the framework developed. The system implements document reader object, data split object, data structure object, coordinate conversion object, pushover animation object, data inquire object and model demonstrate object etc. Users can inquire pushover data while looking at pushover animation in various angles. The result obtained gives a direct visualization to the failure progress of the RC buildings and benefits the engineers a better understanding of seismic behavior for the structures. Through this developed framework, the more accurate seismic characteristics of the RC building can be discussed and the optimal seismic retrofitting of those with insufficient seismic capacity can be determined easier.

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38

Vui, Vu Duy, and 武維樂. "Pushover Analysis of Reinforced Concrete School Building under Earthquake." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/75902948247660321753.

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碩士
國立臺灣大學
土木工程學研究所
102
The problem of seismic assessment of low-rise school buildings is significant in Taiwan after the Chi-Chi earthquake in 1999. The technology of seismic assessment of low-rise school buildings has already been developed in NCREE handbook. However, in design practice, there are still numerous problems that need to be considered. In the study, two pushover tests of school building are compared with the analysis to evaluate the effectiveness of the TEASPA method. Besides, a new method, SERCB, which considers the change of axial force in practical structure when earthquake occurs, is called SERCB, claims to be more efficient in describing the behavior of member in nonlinear analysis. Based on the obtained base shear – roof displacement curve and failure mechanism that are determined from each analysis, this study proposes some recommendations for simulating plastic hinges for members of school buildings.

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39

Liang, Jia-Lun, and 梁嘉倫. "Studies on the Modeling Techniques for NCREE Pushover Analysis." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/91412803138876089330.

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碩士
國立中興大學
土木工程學系所
99
The pushover analysis scheme developed by (NCREE) has been used substantially by engineers to evaluate the earth quake resistance performance and possible rehabilitation for many elementary school and junior high school buildings in Taiwan. However, due to the unreasonable man-made setting or program parameters defined problems, often caused by the user after the execution of the inconsistent results of trouble and should be clarified. Several topics, including modeling of foundations; brick wall equivalence diagonal bracing plastic hinges; basements; RC rehabilitated columns techniques, …, etc. have been studied in this paper. Based upon physical performance, the material properties, element characteristics, structural behavior, as well as the limitations of the analysis programs, and other considerations, it was tried to find more reasonable results to show the seismic capacity of the structures. Results show that: 1. Foundations should be modeled as hinged end with tie beams basis and lateral springs, 2. Brick wall equivalence diagonal bracings should be given with a small tensile capacity, 3. Basement walls should be modeled in different ways to reflect possible short column effects, 4. Extension of the rehabilitated RC column to the footing only affects the distribution of the shear forces and bending moments among the tie beams and the column. No significant difference was observed as far as the seismic performance is concerned.

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40

DUNG, NGO VIET, and 吳越勇. "Seismic Evaluation of Buildings by Multimode Pushover Analysis Method." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/35347841918166156455.

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碩士
國立臺灣科技大學
營建工程系
97
ABSTRACT Pushover analysis procedure (PA) was a very convenient tool for evaluating of seismic performance of buildings by applying the lateral for patterned as the inertia force of the first mode. The procedure has been extended to consider the pushover for multiple modes. The peak inelastic response of a 10-storey, 20-storey steel building (SB) and 5-storey reinforced concrete building (RCB) determined by the approximate MPA procedure is compared with rigorous non-linear response history analysis, it is demonstrated that MPA estimates the response of buildings responding well into the inelastic range to a acceptable accuracy. Moreover, it shows that for the low building (5-storey RCB), the first mode results is dominate while for the higher building (10-20 SB) we need at least 2 modes to converge the results to a certain acceptable errors compared with the results obtained from the RHA procedure. Finally, when comparing the errors of 3 kinds of building: low building, medium building, and high building, that the errors in the low-medium building are quite smaller than the others. Thus, the MPA procedure is a better application for low and medium buildings’ evaluation and design. KEY WORDS: building evaluation and retrofit; modal analysis; pushover; seismic demands.

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41

Lu, Hu-Jhong, and 呂胡忠. "Pushover analysis research of the cracked reinforcement concrete beam." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/55415634292471062292.

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碩士
淡江大學
土木工程學系碩士班
95
The pushover analysis of the seismic damage assessment method is used in analysis of R.C. frame and simulated the seismic behavior of it. And by comparing the capacity curves of tough behavior of structure, we can find the results. Except according to the ATC-40, we simulated the reduction of stiffness with crack of R.C. beam by bending plastic hinge. About the plastic hinge, we applied the SAP2000 to analyze the behavior of cracked R.C. beam and decided the crack according to the stress. Finally, in the results of pushover analysis, we have found that the max. lateral displacement and force will be changed. The purpose of crack simulation is represented the old buildings for more reasonable. By considering the reduction of stiffness with cracked member and leaking, we expected to improve the efficiency and exactitude of the seismic damage assessment method.

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42

Chiang, Yue-Jin, and 江岳錦. "Pushover Analysis for Steel Frames Connected with Corridor Bridges." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/07672835191936489242.

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碩士
朝陽科技大學
營建工程系碩士班
98
Earthquake may cause severe damage to buildings and wounded or dead harm to people. In order to ensure the structural safety of buildings, the lateral limit load capacity of building structure is studied concentrately. In this thesis, the computer program SAP 2000 version 7 was used to analyze the elastic-plastic behavior of two steel frames connected with bridges. The displacement and collapse of buildings linked by corridor in different height, number, length and width and suffered to earthquake were studied. The result showed that the ultimate load of building will be raised if bridge is supported by two inclined rods. But the displacement of building will be decreased when building is subjected to lateral force, such as earthquake load and wind load.

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43

Liu, I.-Te, and 劉一德. "The study on the Pushover Analysis of RC Structures." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/kjf6bc.

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碩士
國立臺北科技大學
土木與防災研究所
96
The major purpose of this research is to study the strong points and weak points of the nonlinear analysis procedure that recommended by FEMA. The analyzed RC structures for comparison are some tested specimens that performed in NCREE. The definition of hinge properties of analyzed structures are according to the regulation of FEMA, the SAP2000 software is adopted for the pushover analysis and to establish the capacity curves. The simulated capacity curves and failure modes of RC structures are compared with those results obtained by cyclic loading tests. This study found that the simulated failure mode can reflect the actual damage conditions by tests, but the simulated capacity curves have significant differences as compared with the test results. The major reason of the differences between simulation and test is that the FEMA’s recommendations have underestimate the residual strength and ductility of the backbone curves of members.

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44

HUANG, WEI-CHING, and 黃韋晴. "Pushover Analysis of Reinforced Concrete Frames Considering Joint Strength Degradation." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/6ydgkk.

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碩士
國立雲林科技大學
營建工程系
105
In recent years, the annual amount of new high-rise buildings increase year by year in Taiwan. The high-rise buildings could alleviate the crowded streets, reduce the use of land and enhance the quality of living space. Landscape has been running sky-high in Taiwan, high-rise buildings seems to be the future of architectural trends. At present time, the earthquake-resistant design of concrete structures is based on capacity design method, and the existing nonlinear models cannot fully consider the nonlinear deformation of the frame joint, resulting in underestimation of the overall deformation and inderstory drift angles. In other words, the nonlinear deformation of the concrete structure may be greater than the analytical prediction, and the existing framework nonlinear analysis model does not correctly consider the possible strength attenuation and failure modes of the framing joints, because engineers use to simulate joints as rigid nodes. The possible joint failure and local collapse are not modeled in practice today. In this study, the behavior of joint shear strength degradation is considered. The non-linear behavior of the joint is modeled by the framing elements connected by a joint panel, which was composed of by pin-connected rid rods and two diagonal equivalent bracings. The joint shear strength of ASCE 41 and ACI 369 is a single nominal strength calculation, if the shear force does not exceed the nominal strength of the joints, the joint is damage free, which cannot simulate the joint shear failure with beam yielding behavior. In this paper, a linear-interpolation strength degradation model is used to model the joint panel resisting shear after beam hinging. The failure modes of the beam-column joint are predicted by semi-empirical formula of the joint shear strength, and corresponding non-linear plastic hinge parameters are defined according to the predicted failure mode. Finally, a total of 64 interior and 15 exterior beam-column joints are modeled to discuss the difference between the experimental and analytical results. More rational prediction can be obtained using the proposed analytical models.

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45

Shen, Yu-Jyun, and 沈裕鈞. "Establishment of Visual Platform (Visual_SERCB) for Pushover Analysis of Building." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/47z7h5.

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碩士
國立臺北科技大學
土木與防災研究所
98
In the past decades, the computer technology got a great progress in the animation of image. With the rapid development in computer science, the 3D animation technology has been significantly applied to create the virtual visualization of reality in many fields from commercial advertising to academic simulations. It can be seen that the visual image technology is getting more and more important in our daily life. The 3D simulating models make a better understanding of virtual visualization of reality. Consequencely, there are many relavent software like as 3D Studio Max, AutoCAD, Maya, etc, that have been developed to reveal 3D animation models easily. This thesis aims at developing a virtual reality system in displaying the failure process of the reinforced concrete (RC) building subjected to earthquake. The system implemented by the language of C# associated with the commercial software 3ds Max serves as the postprocessor of the well known software of seismic evaluation of RC building (SERCB). The propagation of damage for each structural member of the RC building during the pushover process can be shown visually. This thesis helps the engineers realize the seismic behaviors of the building structure.

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46

YU, MING-SIOU, and 余明修. "A Study on Pushover Analysis of the Atypical school Building." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/t56js8.

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碩士
大漢技術學院
土木工程與環境資源管理研究所
105
The pushover analysis of the seismic resistance and reinforcement design in Taiwan is on the basis of the theory of shear build; the methods are SERCB and TEASPA. The analysis of low-rise housing is mostly used TEASPA method. Atypical school building contains special structure types (L type, round, oval, ladder, arc, etc.) often caused the problems of analysis and whether the analysis is correct. Therefore the study is to explore how to accurately analyze seismic resistance of atypical school buildings.

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47

Tseng, Chih-Chien, and 曾至堅. "Seismic Evaluation of Low-rise School Building with Pushover Analysis." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/40552119466456071578.

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碩士
國立成功大學
土木工程學系碩博士班
95
This study uses the capacity spectrum method which was suggested by ATC-40 to evaluate the seismic resistance of a low-rise school building, and introduced the ETABS-Nonlinear analysis as a tool to perform a precise seismic evaluation. The capacity spectrum curve is transferred by the relative curve of the base shear versus the roof displacement through a pushover analysis. From the pushover analysis, the seismic resistance of the structure is not only controlled by the strength but also by the stiffness. 　　According to FEMA-273 and the structure component’s behavior, we develop a reasonable method to define plastic hinge properties for RC columns. Because ETABS cannot to set the plastic hinge properties on the shell element, this thesis provides the equivalent truss mode to simplify the simulation of brick walls. 　　The Nation Center for Research on Earthquake Engineering proceeded a series of static push over experiments for school buildings, we compared the experimental and analytical curves in order to verify the current seismic evaluation method. The results of analysis indicate that the proposed analytical method can simulate the strength and the actual seismic behavior of low-rise school buildings accurately. Then, the seismic evaluation method which suggested by this text can provide the engineers a way to perform precise seismic evaluation.

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48

Wu, Chuan-Yu, and 吳權祐. "Pushover Analysis and Seismic Assessment for Irregular Portal Frame Bridges." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/85593036307983696913.

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碩士
中原大學
土木工程研究所
100
In the literature, the pushover analysis and seismic assessment focused on bridges with single-column-bent piers. In practical, there are many bridges with portal frame piers in Taiwan. In latter cases, the axial forces of the right and left columns are different, which affect the relationship between the moment and curvature of the cross section of each column. The pushover curve is then influenced by the moment-curvature curves of cross sections. Furthermore, the plastic hinges could occur at the top or bottom of each column for bridges with portal frame piers, which increases the complexity of the structural analyses. Besides that, the pattern of lateral force and displacement monitoring point are based on the assumption that responses of the considered structure are mainly controlled by its first mode in traditional pushover analyses. As such, the pushover analysis may not be reliable for the irregular bridges which higher modes are important and the selection of the displacement monitoring point is not easy. In this study, six irregular numerical bridges are established using the commercial finite element software, SAP2000, to carry out the pushover analyses and seismic assessments. The influences of the pattern of lateral load and the selection of displacement monitoring point in the pushover analyses are investigated. In addition, modal pushover analyses (MPA) and simplified modal pushover analyses (SMPA) are carried out to study the effects of higher modes for irregular bridges. Finally, three different seismic assessment methods are discussed and these corresponding results are compared with nonlinear dynamic analyses.

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49

Mahammad, Yaar. "Seismic Performance of Multistorey Reinforced Concrete Buildings By Pushover Analysis." Thesis, 2015. http://ethesis.nitrkl.ac.in/7027/1/Seismic_Muhammad_2015.pdf.

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The buildings are constructed mostly based on the usual standard codes considering the gravity loads consisting of the self-weight of the structure and the live load. These structures are experiencing low magnitude loads in their design life that leads only to the elastic range response, however, strong loads such as a sudden earthquake will lead the structure beyond its elastic limit. The performance of Reinforced Concrete structures will be nonlinear under seismic loads so the nonlinear behavior of reinforced buildings will be defined by the formation of plastic hinges and loss of considerable stiffness. In this case we need a method to evaluate the performance level of the structure in the plastic range, hence we used pushover analysis to evaluate the response of the structure to the lateral loads For the explanation above the best example can be the devastating earthquake of Nepal (25th April 2015) which has affected many buildings constructed based on traditional design codes. So it’s important to use deformation based design to avoid or at least develop the ductile behavior for structure; this will avoid the collapse of the building and will surely ensure life safety. In present study pushover analysis is carried out on G+4, G+11 and G+21 Building situated in New Delhi (Zone IV) according to IS 1893:2002 classification of seismic zones in India. Pushover analysis was performed in SAP2000 after it was designed for gravity loads in STAAD Pro based on IS-456-2000. The pushover curve, capacity spectrum, demand spectrum and Performance point of the building was found from the results of SAP2000 and hence it was concluded that the building response is highly dependent on the materials used in the design. Mostly the failure was noticed in the columns of ground story of the buildings. After using increased amount of reinforcement in the ground story the buildings have reached life safety performance level

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50

Liu, Ying-Chen, and 呂映辰. "On the Study of Pushover Analysis for Seismic Evaluation of Buildings." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/83269810178783155745.

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碩士
國立中興大學
土木工程學系所
105
For many new buildings or old buildings, no matter what kind of earthquake, we still want to know is how much the building can withstand the magnitude of the earthquake will not collapse or damage, and the most common way is to use the side To analyze and evaluate the seismic capacity of buildings, and technology with each passing day, but after all, the use of computational analysis of the seismic capacity is still different from the reality, if the analysis of the value of the larger than the strength is relatively conservative, so this article cited Several methods allow us to analyze the seismic capacity of the assessment to be closer to the strength of the seismic capacity. This paper will introduce the two-way side thrust to confirm the impact of multi-directional seismic energy input, which is different from the traditional one-way push Modal side-by-step analysis to demonstrate that the new building material for irregular buildings or high-rise buildings is much more conservative than single-mode analysis of master mode control. In this paper, we will argue that the distribution of the different vertical forces will converge to the same seismic capability after repeated iterations. In this paper, we will argue that different proportions of vertical forces will be converged to the same seismic capability. The The above-mentioned topics will be studied in this paper, the purpose is to analyze the assessment of the more close to the real and conservative building seismic capacity, detailed methods will be introduced in this article.

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Dissertations / Theses on the topic 'Pushover analysis'

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