The displacementbased adaptive pushover algorithm dap. The displacementbased adaptive pushover analysis dap is one of the performance assessments tool for improving the accuracy of the obtained results of nonlinear static analysis in estimating the seismic demands of the structures. Limits of applicability of conventional and adaptive pushover. At each step of the pushover analysis, a different equivalent sdof system is defined as a function of the actual lateral displacement pattern. Pdf nonlinear static methods are simplified procedures in which the problem of evaluating the maximum expected response of a mdof. As a result, the recent years have witnessed the introduction of the socalled adaptive pushover methods, which, unlike their conventional pushover counterparts, feature the ability to account for the e ect that higher modes of vibration and progressive sti ness degradation might have. Pushover analysis has been gaining importance within the seismic. It is concluded that advanced adaptive pushover analysis often gives results superior to those from conventional pushover. Pushover analysis is a partial and relatively simple intermediate solution to the complex problem of predicting force and deformation demands imposed on structures and their elements by severe ground motion. An extensive series of pushover analysis results, monitored on various levels is presented and compared to inelastic dynamic analysis under various strong motion records, using a new quantitative measure. Pinho, development and verification of a displacementbased adaptive pushover procedure, journal of earthquake engineering, 805 2004 643661. This paper introduces an adaptive pushover analysis method to improve the accuracy of the currently used pushover analysis in predicting the seismic. Assessment of the adaptive pushover analysis using. Verification of displacementbased adaptive pushover through multiground motion incremental dynamic analyses.
Development and verification of a displacementbased adaptive pushover procedure, journal of earthquake engineering, 85, 643661. In order to improve the efficiency of adaptive pushover methods for bridges, various studies have been conducted. In this section, the main features of the adaptive nurbsbased limit analysis, originally. In this paper, two advanced adaptive modal pushovers, namely ssap and fap, have been investigated versus their non adaptive load pattern counterparts. The pushover analysis is then continued with a new lateral load pattern, constructed based on the story displacements obtained from the previous stage. A new enhanced adaptive modal sitespecific spectrabased pushover analysis is proposed, which accounts for the effect of higher modes and overcomes the shortcomings of the fema procedure. Adaptive pushover analysis of irregular rc moment resisting. Geotechnical, geological and earthquake engineering, vol 33.
The recent drive for use of performance based methodologies in design and assessment of structures in seismic areas has significantly increased the demand for the development of reliable nonlinear inelastic static pushover analysis tools. An energy based approach, proceedings of the twelfth european conference on earthquake engineering 2002. F a displacementbased adaptive pushover for assessment of. The adaptive pushover algorithm described in the companion paper antoniou and pinho, 2004, initially developed for forcebased applications. In the end, the paper makes recommendations on the methodology of design and the most appropriate strategy of retrofitting these kinds of structures in order to achieve the required level. The procedure encompasses some adaptive pushover analyses. It is made by the hypothesis that the angle of earthquake input of the structure is a random variable. First, an adaptive singlemode pushover analysis using the first mode shape is performed.
A displacementbased adaptive pushover for assessment of buildings and bridges. Introduction one of the emerging fields in seismic design of structures is the performance based design. The load is given as the increment and the modal conditions are changed. Application of normal flow algorithm in modal adaptive. An adaptive capacity spectrum method for assessment of. Nonlinear static analysis pushover assumes that response is governed by a single mode of vibration, and that it is constant during the analysis distribution of lateral forces applied at storey masses.
Jul 22, 2017 the displacementbased adaptive pushover analysis dap is one of the performance assessments tool for improving the accuracy of the obtained results of nonlinear static analysis in estimating the seismic demands of the structures. A shearbased adaptive pushover procedure for moment. A n i n n o v a t i v e d i s p l a c e m e ntb a s e d a d a p t i v e p u s h o v er pushover analysis a major challenge in performancebased engineering is to develop simple, yet. The consideration of response modification factor of lshaped structures by using adaptive pushover analysis method and comparison with traditional pushover method. In madp procedure, each multistage pushover analysis starts with the lateral load pattern proportional to the elastic modeshape vector s n m. A newly derived assessment procedure is proposed within the scope of bridge applications, based on an innovative displacementbased adaptive pushover technique. Request pdf applying adaptive pushover analysis to estimate incremental dynamic analysis curve to estimate seismic demand and capacity of structures, it has been suggested by researchers that. Pdf the consideration of response modification factor of. Another class of enhanced pushover methods is the adaptive pushover procedures. An energy based adaptive pushover analysis for nonlinear static procedures.
Kalkan and kunnath 2006 proposed an adaptive modal pushover analysis based on incremental loading and combination adaptive coupled. An energy based adaptive pushover analysis for nonlinear. A modeadaptive pushover map procedure, which uses a stiffnessdependent lateral force distribution at each loading step without the eigenvalue analysis. This paper intends to perform a seismic risk analysis suitable for vielha hospital and understand the behavior of this. This paper introduces an adaptive pushover analysis method to improve the accuracy of the currently used pushover analysis in predicting the seismicinduced dynamic demands of the structures. The predictions of the omap method are compared to results derived by other recent adaptive pushover methods and rigorous non linear time history analysis. In this paper, 5 storey l shaped rc frame is analyzed for seismic zone iv and designed as per provisions of is codes. In these methods, the effect of higher modes is included in the analysis and the pushover load is considered a function of the updated modal characteristics of the structure.
Conventional and adaptive pushover procedures against dynamic analysis barbara ferracuti, marco savoia, roberto francia. V f a displacementbased adaptive pushover for assessment of buildings and bridges rose school. The pushover analysis from basics presented by rahul leslie 41. Pdf in this paper, a methodology is suggested and tested for evaluating the relative performance of conventional and adaptive pushover methods for. Seismic performance of historical masonry structures. In order to consider such effect, an adaptive version of the capacity spectrum method acsm is proposed. Demand is based on matching modal pushover curves to constant ductility spectra at the pushover ductility. In this method, the newtonraphson iterative algorithm is used along the flow path normal to the davidenko curves with modified convergence rate. Conventional and adaptive pushover procedures against dynamic analysis.
Antoniou and pinho 2004a explored the accuracy of forcebased adaptive pushover analysis in predicting the horizontal capacity of reinforced concrete buildings. Comparative study between conventional and adaptive pushover. The proposed adaptive energybased pushover analysis aepoa not only include the internal structural properties in lateral force that is applied at each step, but. Adaptive load patterns versus nonadaptive load patterns for. An accurate estimation of the applied load pattern is an essential component in each pushover procedure. Evaluation of conventional and adaptive pushover analysis ii. Moreover, a further assessment of the reliability of the approach can be achieved by comparing the collapse load multiplier obtained by means of adaptive limit analysis and the peak load of the pushover curve. The proposed adaptive energybased pushover analysis aepoa not only include the internal structural properties in lateral force that is applied at each step, but also the expected kinetic energy of the motion of the. In other words, the applicability of pushover analysis in predicting. On the pushover analysis as a method for evaluating the seismic response of rc buildings p. Adaptive forcebased multimode pushover analysis for. The pushover analysis from basics presented by rahul leslie 42. This procedure is an adaptive version of the singlerun multimode pushover smp procedure that it is envisaged to be an enhancement of the previously proposed procedure.
Evaluation of conventional and adaptive pushover analysis i. The displacement based adaptive pushover dap technique is an improved pushover. A number of recent studies raised doubts on the effectiveness of conventional pushover methods, whereby a constant incremental force vector is applied to the structure, in estimating the seismic demandcapacity of framed buildings subjected to earthquake action. As a result, the recent years have witnessed the introduction of the socalled adaptive pushover methods, which. Adaptive procedures have been proposed by bracci et al. A n i n n o v a t i v e d i s p l a c e m e ntb a s e d a d a p t i v e p u s h o v er f. Recently, a number of adaptive pushover methods have been proposed in which the effects of the higher modes as well as the progressive changes in the dynamic characteristics of structures are taken into account to compute the applied load pattern.
Comparative results 1 structural capacity, results show that the adaptive method produces. Adaptive load patterns versus nonadaptive load patterns. As a result, the adaptive pushover methods have been developed during the last decade, which unlike their conventional pushover counterparts, feature the ability to account for the effect that higher modes of vibration and progressive stiffness degradation might have on the. Pdf evaluation of conventional and adaptive pushover analysis i. A new displacementbased algorithm for the adaptive pushover analysis of masonry walls and buildings is presented. Structural engineering and geomechanics pushover analysis of building structures sashi kunnath encyclopedia of life support systems eolss pushover analysis mpa and upperbound pushover analysis ubpa procedure are also examples of this approach. Features of the proposed procedure include its similarity to traditional response spectrumbased analysis and the explicit consideration of ground. This novel adaptive pushover method is therefore shown to constitute an appealing displacementbased tool for structural assessment, fully in line with the recently introduced deformation and performanceoriented trends in the field of earthquake engineering. Adaptive pushover analysis for the seismic assessment of. In this paper, a methodology is suggested and tested for evaluating the relative performance of conventional and adaptive pushover methods for seismic response assessment. Adaptive spectrabased pushover procedure for seismic.
Feb, 2016 the pushover analysis from basics presented by rahul leslie 41. Irtem, an effective load increment method for multi modal adaptive pushover analysis of buildings, structural engineering and mechanics, 251 2007 5373. Segment oa has time period ta, curve a representing the rs curve and saa is the lateral load demand, in its elastic range. Pdf conventional and adaptive pushover procedures against. The currently available assessment procedures have been tested predominantly against building frames. Adaptive pushover analysis article pdf available in asian journal of civil engineering 83. An improved displacementbased adaptive pushover procedure.
Pushover analysis for seismic assessment and design of structures spyridon themelis a dissertation submitted for the partial fulfilment of the requirements for the degree of doctor of philosophy heriotwatt university school of the built environment october 2008. As traditional pushover analysis is widely used for design and seismic performance evaluation purposes, its limitations, weaknesses and the accuracy of its predictions in routine application should be identified by studying the factors affecting the pushover predictions. Pdf verification of displacementbased adaptive pushover. Analysis procedures to estimate seismic demands for buildings. They proposed a forcebased adaptive pushover fap which is an extended version of the fully adaptive pushover algorithm proposed by elnashai 2001. In this paper, a load increment method for modal adaptive pushover analysis mapa for plane frame buildings is presented. Limits of applicability of conventional and adaptive. Modeadaptive pushover analysis for multistory rc buildings.
Author links open overlay panel maysam jalilkhani a seyed hooman ghasemi b masood danesh a. Displacement is based on pushover with step size based on constant energy. Evaluation of conventional and adaptive pushover analysis. Adaptive pushover analysis for rc buildings considering. A multimode adaptive pushover procedure for seismic. In this paper we investigate the response modification factor in lshaped geometric asymmetry by using sap software, pushover analysis used in this study is divided into two categories pushover with constant load pattern traditional method and pushover with the adaptive load pattern adaptive. Moghadam 3 abstract in recent years adaptive pushover analysis proposed to overcome the some weaknesses of traditional pushover procedures. Seismic design of an irregular structure with adaptive. Pushover analysis is one of the analysis methods recommended by eurocode and fema 273. A nonadaptive displacementbased pushover procedure for the nonlinear static analysis of tall building frames, engineering structures, 126, 586597. The consideration of response modification factor of lshaped. Displacementbased adaptive pushover analysis dap is one of the performance assessment tools for improving the accuracy of the obtained results of the nonlinear static analysis in estimating the.
This latter application may be very useful to calibrate the load pattern distribution to be adopted in pushover analyses. 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. Adaptive pushover could consider the higher modes effects, and the. In order to evaluate the efficiency of the procedures, three momentresistant steel frames of sac group, sac3, sac9 and sac20, are chosen. Simplified seismic evaluation of structures using adaptive. Analysis ida envelopes, as well as restrict states. Therefore, the primary goals of this paper will be to analyze and compare performances of proposed adaptive pushover analysis pinho and antoniou, 2004b. Comparative study between conventional and adaptive. F a displacementbased adaptive pushover for assessment.
In this study, a new adaptive procedure called energybased adaptive pushover analysis eapa is implemented based on the work done by modal forces in each level of the structure during the analysis and is examined for steel moment resisting frames smrfs. A multimode adaptive pushover analysis procedure for estimating the seismic demands of rc momentresisting frames. Earthquake engineer pushover analysis dynamic nonlinear analysis seismic. A multimode adaptive pushover analysis procedure for.
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