Comparative study of nonlinear static pushover analysis. For the pushover analysis we will use a displacement control strategy. Practical three dimensional nonlinear static pushover an. The analysis was performed using the sap2000 software for the four methods. It helps in understanding the deformation and cracking of a structure in case of earthquake and gives you a kind of fair unders. Introduction one of the emerging fields in seismic design of structures is the performance based design. In other words, the applicability of pushover analysis. Displacement based design, dbd, nonlinear static pushover.
Nonlinear pushover analysis serves the basis for determining the capacity of the structure in terms of base shear and roof displacement when displacement based approach is adopted. Conference paper pdf available january 2011 with 329 reads how we. Nonlinear static analysis, or pushover analysis, has been developed over the past twenty years and has become the preferred analysis procedure for design and seismic performance evaluation purposes as the procedure is relatively simple and considers postelastic behavior. Pushover technical knowledge base computers and structures. Push over analysis require considerable amount of understanding of the subject by the engineer.
In the present research, a statistical verification of conventional and adaptive pushover methods for rc frame structures has been carried out. Pushover analysis is a nonlinear, static structure analysis, which enables presenting structure behavior caused by different types of loads resulting from an earthquake. An alternative method for the determination of inelastic. In displacement control we specify a incremental displacement that we would like to see at a nodal dof and the strategy iterates to. The performance based plastic design is a displacement based method which uses preselected target. An improved displacementbased adaptive pushover procedure. Section analysis software ucfyber is used to analyze the bending moment and curvature performance of columns sections, based on this, a new calculation method of target displacement of rc bridge columns is educed.
Previous displacement based design efforts were based on the direct displacement based. Evaluation of displacement based methods and computer software for seismic analysis of highway bridges author. Opensees finite element software package is used to perform the numerical and nonlinear analyses. A secondary objective was to identify the fundamental differences between force based and displacement based methods of analysis, particularly as they apply to highway bridges. Effect of elevational and member damage on jacket strength. Citeseerx assessment of the adaptive pushover analysis. Seismic analysis nonlinear static analysis pushover. A comprehensive study of displacement based design for reinforced concrete bridge columns is conducted. Interventions were designed, and the resultant building capacity determined using a displacement based. The nsps for the seismic assessment of bridges are generally based on two classic pushover procedures.
The lateral rotation couple effect on structures asymmetric plan was considered using the energy based model pushover analysis mpa procedure. Alternatives considered include force and displacement based procedures. Sep 05, 2015 one of the results of nonlinear static analysis is load displacement chart or capacity curve achieving base shear to displacement and it is called push over curve and with high speed of this analysis compared to other analyses, with displacement of floors and other parameters, has received much attention from engineers. The nonlinear time history analysis nltha of seismic evaluation of a structure is precise, but tedious and requires a lot of data and human skill. Pushover analysis does not create good solutions, it only evaluates solution. However, the procedure involves certain approximations and. The previous studies about pushover analysis are almost based. Then based on a nonlinear push over static analysis and cyclic analysis the seismic parameters such as hysteretic behavior and dissipated energy are compared. Pdf application of nonlinear static pushover procedure. The capacity spectrum method csm, a performance based seismic analysis technique, can be used for a variety of purposes such as rapid evaluation of a large inventory of.
Protastructureopensees integration provides new features for nonlinear analysis of structures. A number of recent studies raised doubts on the effectiveness of conventional push over methods, whereby a constant incremental force vector is applied to the structure, in estimating the seismic demandcapacity of framed buildings subjected to earthquake action. The analysis and design of the strengthening of the building was completed by an average practicing engineer using a displacement based method. Based on these conclusions, they adopted and developed the displacement based. Protastructureopensees integration provides new features for nonlinear analysis of. Pushover is a staticnonlinear analysis method where a structure is subjected to gravity loading and a monotonic displacementcontrolled lateral load pattern which continuously increases.
Displacementbased seismic analysis, forcebased seismic no restrictions. Pushover analysis is one of the analysis methods recommended by eurocode and fema 273. The simple mathematical model is introduced by an sdof model, which is based on the results of pushover analysis of the mdof model. In this case, the target displacement found from the pushover analysis should be. Static pushover methods explanation, comparison and. Kheiri and bahaari 2006 with using abaqus software performed pushover and nonlinear dynamic analysis for two platforms. Target displacement calculation for push over analysis. Nonlinear pushover analysis for pile foundations 6 0 20 40 60 80 100 120 140 160 0 100 200 300 400 500 600 700 800 lateral displacement mm horizontal shear kn total load left pile middle pile right pile figure 3.
This work presents the nonlinear pushover procedure, which is based on the n2 method. Introduction to pushover analysis and capacity spectrum. This video introduce a brief summary to the procedures of pushover analysis and capacity spectrum method. In displacement control we specify a incremental displacement that we would like to see at a nodal dof and the strategy iterates to determine what the pseudotime load factor if using a linear time series is required to impose that incremental displacement. From output nonlinear analysis, we compare base shear and displacement in bare frame, in fill wall frame and ground, it seen that at roof level, displacement in bare frame is more than other two frames and. As the name states push over, push the building until you reach its maximum capacity to deform. Study of rc framed structure using push over analysis. Both methods consider a single mode and keep the shape of the pushover load distribution constant during the analysis. Comparison of static against dynamic results, in terms of capacity curves, interstorey drift profiles and failure modes, seems to lead to the conclusion that displacement based adaptive pushover usually features the highest potential to better reproduce results of incremental dynamic analysis. 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. Presented in this paper is the comparison of a steel moment resisting frame designed by the performance based plastic design method and conventional elastic design method based on the seismic evaluation done by both nonlinear static push over analysis and nonlinear dynamic analysis time history analysis under different ground motions using the sap2000 software. Evaluation of energy based pushover analysis procedure for. Push over analysis for concrete structures at sesimic zone3. Force based pushover analysis of seismically deficient r.
Displacementbased pushover analysis of a masonry arch bridge. A large number of simulated response spectrum compatible timehistories has been used to perform incremental dynamic analyses. Assigning nonlinear properties to the hinges force displacement or momentrotation diagrams. Assessment of the adaptive pushover analysis using.
Displacementbased seismic analysis of a mixed structural. Displacement based approach tends to give realistic idea of demand over the structure as it uses roof displacement as preliminary input parameter. Displacement based assessment and improvement of a typical. Evaluation of displacementbased, forcebased and plastic. First, a pushover analysis of the ctv building was performed. We can either model the structure as a spine model frame or a 2d or 3d finite element model. Push over analysis on existing bridge abdul raheem1 amaresh s patil2 1,2department of civil engineering 1m tech student 2associate professor 1,2h. The simplified design code based displacement analysis procedure according to romanian seismic design code p100 20annex e and ec8 4 chapter 4. How to decide the target displacement in the displacement controlled pushdown analysis. The idcm method is a procedure in the field of seismic analysis of structures based on the nonlinear static pushover analysis.
Comparison of elastic design and performance based plastic. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Fu and hamed alayed, university of maryland abstract nonlinear static pushover procedure is specified in the. This study evaluates the seismic demands for three dimensional unsymmetricplan buildings determined by the displacement based adaptive pushover dap analysis. Current practices, however, are based on plastic nonlinear analysis. Defining nonlinear hinges in a structure calculation model. Pushover analysis an overview sciencedirect topics.
Displacementbased seismic analysis of a mixed structural system jane li. Performance based plastic design pushover analysis is performed by displacement coefficient method or capacity spectrum method. Verification of displacementbased adaptive pushover. By using displacement analysis, a hotel can calculate the value of the group booking compared to what transient and walkin bookings would generate by contrast. Perform3d includes powerful tools that assess the performance of a structure, and hence support design. The pushover analysis, explained in its simplicity alacero. Also in nonadaptive pushover methods, force based loading would reach to better results. Evaluation of energy based pushover analysis procedure. Even in advanced pushover methods, little attention has been paid to the unsymmetric structures. Capacity and performance based design of bridges istanbul computer and structures, inc. Evaluation of displacementbased methods and computer software.
Perform analysis of the model based on analysis cases bridge experts can use csi bridge templates for generating bridge models, to analysis the point load, wearing load, wind load for height portion to evaluate push over analysis. Push over analysis uses a single response spectrum to represent the several ground motions, and uses this spectrum and the push over curve to estimate the average of the maximum displacements caused by the earthquakes. Strength drop, displacement control, and all other nonlinear software. The three software to be used in the pushover analyses are. Where can i find a detailed example of pushover analysis. In addition, for the shear wall model an elastic analysis with ductility factors applied was also performed. The pushover analysis consists of the several stages listed below. A push over process was completed using microstran, and models of postyield behaviour were developed. The base shear force displacement relation at level 1 is shown in fig. The problem is that the resulting interstory drifts ive obtained with it, doesnt accord very well with those of the non linear time history analysis. Momentcurvature analysis determines the inelastic properties of a reinforced concrete crosssection to establish the displacement capacity using pushover or time history analysis. The atc40 and fema273documents have developed modeling procedures, acceptance criteria and analysis procedures for pushover analysis. Pushover is a staticnonlinear analysis method where a structure is subjected to gravity loading and a monotonic displacement controlled lateral load pattern which continuously increases through elastic and inelastic behavior until an ultimate condition is reached.
This paper presents a new methodology for the displacementbased seismic design of symmetric singlestorey woodframe buildings. Pushover analysis is approximate in nature and is based on static loading and it cannot represent the dynamic phenomena with a large degree of accuracy. Evaluation of displacementbased methods and computer. Displacement based assessment and design is always challenging issue for structural engineers. A multimode adaptive pushover procedure for seismic. Displacement based 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. Push over analysis of the wharf structure, pinned pilewharf connections. Displacementbased seismic design of symmetric single. Pushover analysis for performancebased seismic design. Modeling of the steel frame structure under the push over analysis using seismostruct software and the results so obtained has been compared.
Reliability analysis in performancebased earthquake engineering. Displacement based pushover analysis of a masonry arch bridge structural nonlinear static bridge masonry displacement based pushover. Pc software 1 has the capability to run such analyses, both in 2d and 3d. On sa, the analysis results are always the elastic limit state forces moment, shear and axial forces to be designed for.
The program has become the standard analysis software in slovenian. Static pushover analysis is an attempt by the structural engineering profession to evaluate the real strength of the structure and it promises to be a useful and effective tool for performance based design. 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. This paper evaluates accuracies and applicabilities of frame elements constructed by displacement based db, force based fb and plastic hinge ph. The method used to make this judgement is called displacement analysis. Ive developed a script to perform a displacement based pushover. Application of nonlinear static pushover procedure to the. One of the results of nonlinear static analysis is load displacement chart or capacity curve achieving base shear to displacement and it is called pushover curve and with high speed of this analysis compared to other analyses, with displacement. An improved displacement based adaptive pushover procedure for the analysis of frame buildings reza abbasnia department of civil engineering, iran university of science and technology. Pushover curve or capacity curve is a graph of base shearv vs.
A displacement based adaptive pushover algorithm for assessment of vertically irregular frames of the fourth european workshop on the, 2005. Performance based structural engineering pbse is not new. Results show that the estimated rsr by nonlinear dynamic analysis was higher than estimated rsr by static pushover analysis method and in both methods local failures occurred before total loss. Displacementbased design for rc bridge columns based on. 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. College of engineering, gulbarga abstractthe aim of the project is to carry out a seismic evaluation case study for an existing rc bridge using.
Reinforced concrete frame pushover analysis openseeswiki. Displacementbased seismic design of a large naval pier. In pa, in the global sense, it is the base shear vb vs roof top displacement. Ppt pushover analysis powerpoint presentation free to. Performing structure modal analysis to determine one mode. Based on the results of the displacement analysis, it can then make a decision on whether to accept a group. Based on displacement based seismic design concepts, this paper. Software used for analysis is finite element based software. The paper presents a simple computer based push over analysis technique for performance based design of building frameworks subject to earthquake loading. Revenue management between displacement calculation and analysis. 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.
Features performancebased design software perform3d. Pushover analysis the analyses are carried out for various nonlinear condition and the following parameters are compared namely. Soilstructure interaction, pushover analysis, material overstrengths, and sitespecific response spectra are used to determine the displacement response of the pier under levels 1 and 2 earthquakes, the displacement. Investigation on performance levels of 8storey rc building.
Displacement analysis definition glossary for hotel revenue. The base shear forcedisplacement relation at level 1 is shown in fig. If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Seismic behavior evaluation of knee braced frames based on. The dc ratios for performance assessment are calculated at this displacement. The example was calculated manually in chapter 5, here the analysis is by the software. Pushover analysis of the mdof model was performed for the weak direction only since the mathematical model of the test structure, too, was subjected only to ground motion records in the weak direction. The target displacement level is determined by using a double. A displacementbased adaptive pushover algorithm for assessment of vertically irregular frames of the fourth european workshop on the, 2005. Conclusions are drawn based on the target displacement of the structure by using idealized forcedisplacement curve.
The difference is in pushover you try to get the capacity of the building for maximum displacement and in seismic analysis you try to keep your displacements. Limitanalysis based solutions are considered trustworthy to investigate collapse mechanisms in masonry structures, even though they cannot be used in displacementbased seismic assessment. The results of an analysis are useful only if they are presented in a way that supports decision making for design. Seismic analysis nonlinear static analysis pushover and. Seismic analysis generally is a dynamic analysis which may be linear or nonlinear while pushover is a nonlinear static analysis. Analysis results including fundamental period, base shear. Pushover analysis is one of the mostused nonlinear static procedures for the seismic assessment of structures, due to its simplicity, efficiency in modeling and low computational time. 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.
Pushover is a staticnonlinear analysis method where a structure is. Seismic analysis of bridges using displacementbased approach by chung c. Elastic displacement response spectrum, inelastic displacement. Pdf comparative evaluation of displacementbased vs. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over. Soilstructure interaction, pushover analysis, material overstrengths, and sitespecific response spectra are used to determine the displacement response of the pier under levels 1 and 2 earthquakes, the displacement demand. Consequently, when only nonadaptive static nonlinear analysis tools are available, as has been the case throughout the past, force based pushover does constitute a preferable choice over its displacement based counterpart. Pushover analysis was carried out for the basefixed superstructure to. Push over analysis for concrete structures at sesimic zone3 using etabs software written by g. The present study develops a push over analysis procedure based on a continuous nonlinear postelastic material model, which provides the capacity to monitor initial yielding and gradual progressive behaviour of both individual elements and overall structural systems. Dec 15, 2014 revenue management between displacement calculation and analysis. Seismic analysis of bridges using displacementbased. Incremental loads based on the a i distribution were applied in the east, west, south, and north directions to observe the differences in static responses around the northwall complex.836 1165 550 1016 824 664 307 1530 387 745 50 707 79 384 969 443 1459 719 535 1559 857 804 835 944 1267 1604 317 140 1101 408 1044 529 38 977 1235 553 1097 1159 386 1102 18 709 1405 898