Comparison of the pseudostatic and dynamic behaviour of. You can define the value per phase via the model conditions pseudostatic option in the model explorer. When pseudostatic analysis is not enough low frequency vibrations can normally be calculated with a pseudostatic analysis, by default available in plaxis, however for more advanced seismic analysis the dynamics module is. In this study, the upper san fernando and kitayama earth dams, which have been designed using the pseudostatic approach and damaged during the 1971 san fernando and 1995 kobe. This tool is an extension of compiler technology or sometime compiler also came along with this analysis feature.
Seismic displacement of gravity walls had been studied using conventional static methods for controlled displacement design. The experimental results confirm the predictions of stress limit analysis and concluded that the pseudo static stability analysis performs adequately for both harmonic and seismic excitations. Residual deformations are also estimated using newmarks sliding block method. Two options are available for calculating the undrained strengths prior to the application of the seismic forces. Plaxis 3d infrastructure and engineering software and. Plaxis 2d software accomplishes the analysis of retaining wall in static and seismic conditions. Nevertheless, the straightforward pseudostatic analyses need a careful. Stagedthepseudostaticbaseanalysis a staged pseudostatic analysis involves the completion of two stability analyses for every single slip. The pseudostatic approach mononobe 1929 and okabe 1924 and displacement approach newmark 1965 are common and classic methodologies in practical analysis and design of retaining structures, including mse walls.
Aug 16, 2019 slopes can be analysed in either direction, and a seismic coefficient is provided for pseudo static analysis. In the pseudo static analysis, the peak ground acceleration is converted into a pseudo static inertia force and applied as a horizontal incremental gravity load. A numerical simulation on the dynamic response of mse wall. In this study plain strain numerical analysis is performed using plaxis dynamic program where prescribed displacement is applied at the bottom boundary of the soil to simulate the applied seismic load. Procedures for estimating seismicinduced permanent. When pseudo static analysis is not enough low frequency vibrations can normally be calculated with a pseudo static analysis, by default available in plaxis, however for more advanced seismic analysis the dynamics module is required. Developer mostly uses the static analysis tools just to test software component and development process. Pseudostatic lateral analysis technical knowledge base. The software is equipped with advanced features to tackle modeling challenges in. Pseudostatic and dynamic nonlinear finite element analyses have been performed to assess the dynamic behaviour of gravity retaining walls subjected to horizontal earthquake loading. College of engineering, ahmedabad, india abstractthe slope stability is a very important problem in geotechnical engineering. Slopew and plaxis are two common software programs currently employed by geotechnical engineers within australia and other countries. Pseudostatic earthquake analysis, block slip analysis, bearing capacity analysis and probability.
Lowfrequency vibrations can normally be calculated with a pseudo static analysis by default available in plaxis. Pseudo static and dynamic nonlinear finite element analyses have been performed to assess the dynamic behaviour of gravity retaining walls subjected to horizontal earthquake loading. Dynamic analyses were conducted to simulate the earthquakeinduced deformations of the san fernando dam using plaxis software. Forcebased pseudostatic methods as the one implemented into plaxis represents the effect of complex, transient, dynamic effects of earthquake shaking by constants inertial forces, which are incrementally applied to the whole mesh. In this study we try to approach the gained forces by pseudostatic method according to fhwa code and gained forces from numerical modeling by finite element method, by selecting seismic horizontal coefficient for different wall height. Pseudostatic and pseudodynamic stability analysis of. Plaxis 3d bentley infrastructure and engineering software. Performancebased seismic analysis of an anchored sheet. Cgdams is a finite element based program written specifically for the stability analysis of concrete gravity dams. The pseudo static approach mononobe 1929 and okabe 1924 and displacement approach newmark 1965 are common and classic methodologies in practical analysis and design of retaining structures, including mse walls. First phase is dam plastic analysis conducted for the time when the construction is over.
In earthquake engineering to analyze the seismic response of soil embankments and slopes simply adding a permanent body force representing the earthquake shaking to a static limitequilibrium analysis. Finite element methods against limit equilibrium approaches for slope stability analysis h. Seismic displacement of gravity retaining walls sciencedirect. The numerical calculations using plaxis software involve 3 phases. In plaxis 2d and plaxis 3d a pseudo static acceleration can be defined per phase in the model conditions pseudostatic option in the model explorer figure 1. Stagedthepseudostaticbaseanalysis a staged pseudo static analysis involves the completion of two stability analyses for every single slip. The plaxis interface guides you across several modes to efficiently create models with a digital geotechnical workflow. Dave2 1pg student 2professor 1,2department of applied mechanics 1,2l. Displacements obtained from pseudostatic slope analysis.
On the use of soil drained and undrained parameters. When using numerical modeling software such as plaxis 2d to model slope stability or a tall retaining wall with seismic loads, a quick method is to use the pseudo static acceleration as opposed to several time histories and full dynamic analysis. Comparison du logiciel geotechnique geo fem, plaxis, zsoil j. Pseudostatic and pseudodynamic calculations are applied to obtain the critical acceleration. Mar 02, 2017 i have rarely use abaqus so can not tell much about that.
The retaining wall with backfill material was analysed with inclusion of. Pseudostatic analysis this approach consists of performing a slope stability analysis, usually by the limit equilibrium method, where a 2d fos is computed in which a static horizontal inertial force is applied to the potential sliding. Plaxis 2d dynamics is an addon module to plaxis 2d. Researchers have also used the finiteelement method to analyze retaining systems and have developed computer software. The static analysis tool is software which works in a nonrun time environment.
Nucifora1 1centre for built infrastructure research, school of civil and environmental engineering, the university of technology sydney uts, p. Pseudo static acceleration and model size slope stability. Jun 30, 2018 a key feature of the software plaxis 3d foundation. Lowfrequency vibrations can normally be calculated with a pseudostatic analysis by default available in plaxis. Plaxis sometimes stylised plaxis, plane strain and axial symmetry, indicating the geometric types handled in the original code is a computer programme that performs finite element analyses fea within the realm of geotechnical engineering, including deformation, stability and water flow. In most cases the analysis is performed on some version of the source code, and in the other cases, some form of the object code the term is usually applied to the analysis. Complementary is the conclusion that plaxis 2d pseudostatic approach proves to be suitable to determine the critical acceleration of an.
Evaluation of the accuracy of the pseudostatic approach is governed by the accuracy with which the simple pseudostatic inertial forces represent the complex dynamic inertial forces that actually exist in an earthquake. Then the pseudostatic seismic coefficient used in the design and analyses of the. What is the best software to analyse the slope stability. Slopew can effectively analyze both simple and complex problems for a variety of slip surface shapes, porewater pressure conditions, soil properties, and loading conditions. Plaxis 2d dynamic loading modelling software by plaxis. Slopes can be analysed in either direction, and a seismic coefficient is provided for pseudostatic analysis. With the dynamics module plaxis 2d and 3d are extended with capabilities to. Comparison of geotechnic softwares plaxis, zsoil and geo mkp. Pdf pseudostatic analysis of piles in different soils researchgate. Plaxis 3d allows you to make safe, costefficient decisions that offer fast, comprehensive analysis methods in a userfriendly platform.
Comparison of geotechnic softwares plaxis, zsoil and. Apr 17, 2014 in plaxis 2d and plaxis 3d a pseudo static acceleration can be defined per phase. Limitstate analysis method based on pseudostatic approach is among several methods that have been used to study seismic stability of gravity retaining walls mononobe, and matuo. Multistage pseudostatic analysis geoslope international. Plaxis 3d is further enhanced with plaxflow for groundwater flow and dynamics for dynamic load modeling. Pseudostatic and dynamic analysis, including dynamics. In addition to static loads, the dynamic module of plaxis also provides a powerful tool in modeling the dynamic response of a soil structure during an earthquake. Plaxis 3d is one of the most trusted software to handle this complex geotechnical problem.
In plaxis 2d and plaxis 3d a pseudo static acceleration can be defined per phase in the model conditions pseudostatic option in the. Pdf pseudostatic and dynamic analyses of tunnels in trasversal. In this study we try to approach the gained forces by pseudo static method according to fhwa code and gained forces from numerical modeling by finite element method, by selecting seismic horizontal coefficient for different wall height. Static program analysis is the analysis of computer software that is performed without actually executing programs, in contrast with dynamic analysis, which is analysis performed on programs while they are executing. Fem is better for the static problem meanwhile the fdm. Jun 22, 2009 in the pseudo static analysis, the peak ground acceleration is converted into a pseudo static inertia force and applied as a horizontal incremental gravity load. Evaluation of the pseudostatic analyses of earth dams. The typical section of a 29 feet high wall for the winslope analysis is modeled in plaxis. Delft university of technology model solutions for performance. A pseudo static approach is a strongly simplified approach of an earthquake situation. The experimental results confirm the predictions of stress limit analysis and concluded that the pseudostatic stability analysis performs adequately for both harmonic and seismic excitations. Low frequency vibrations can normally be calculated with a pseudostatic analysis, by default available in plaxis, however for more advanced seismic analysis the dynamics module is required. The fe software plaxis v8 brinkgreve, 2002 has been used to.
Slope stability analysis slopew is the leading slope stability software for soil and rock slopes. We use cookies to provide you with the best possible user experience. Second phase includes dam plastic analyses under own body load and finally the last step consists of dynamic analysis under earthquake loading. I need to run a pseudostatic lateral analysis in which structural inertia represents the earthquake load. Low frequency vibrations can be calculated with a pseudostatic analysis. In this approach, we apply a constant and uniform acceleration to all the mass in the model. How does plaxis deal with water pressures during dynamic. Pseudo static analysis this approach consists of performing a slope stability analysis, usually by the limit equilibrium method, where a 2d fos is computed in which a static horizontal inertial force is applied to the potential sliding. Finite element methods against limit equilibrium approaches. Low frequency vibrations can normally be calculated with a pseudo static analysis, by default available in plaxis, however for more advanced seismic analysis the dynamics module is required. Depends on what outputs you require from your analysis. The input procedures enable the enhanced output facilities provide a detailed presentation of. Design and analysis of three different kinds of candles workflow geotechnical logical tunnel design threedimensional enter the options cad tool for calculating the structural forces of the volume of a cylinder, the size of the pile quasistatic analysis define alpha coefficient.
Between flac and plaxis, flac base on fdm analysis meanwhile plaxis base on fem analysis so they inheritance their parent properties. Rational pseudostatic stability analysis of embankments. If you continue to use the site without changing your cookie settings, we assume you are fine with our cookies and the way we use them. However, for more advanced seismic analysis, choose the plaxis 2d dynamics module. Apr 18, 2020 forcebased pseudo static methods as the one implemented into plaxis represents the effect of complex, transient, dynamic effects of earthquake shaking by constants inertial forces, which are incrementally applied to the whole mesh. The effects of vibrations have to be calculated with a dynamics analysis when the frequency of the dynamic load is in the order or higher than the natural frequency of the medium. Geo fem is geotechnical software based on the finite element method utilized friendly platform from geo4 programs. For geosynthetic reinforcement, it uses soilreinforcement interaction coefficients in combination with stress conditions at the slip surface to. I need to run a pseudo static lateral analysis in which structural inertia represents the earthquake load. In modelling the dynamic response of a soil structure, the inertia of the subsoil and the. The minimum values of factor of safety using pseudostatic and pseudodynamic method are obtained as 1.
If you need only factor of safety in static condition, slide limit equilibrium based software, phase2 fem, flac fdm, plaxis fem are. Software, lem, fem, slope stability, plaxis analysis of slope stability when it is subject to various types. In the pseudostatic analysis, the peak ground acceleration is converted into a pseudostatic inertia force and applied as a horizontal incremental gravity load. The code automates the prediction and evaluation of cracking in the dam, along the damrock interface, and in the foundation using incremental nonlinear analysis techniques based on. Plaxis 2d dynamics reliable and comprehensive dynamic loading modeling in 2d. In the dynamic analysis, an actual measured earthquake acceleration time history has been scaled to provide peak ground acceleration values of 0. In plaxis 2d and plaxis 3d a pseudo static acceleration can be defined per phase.
Phreatic surface is generated using seepage analysis in geotechnical software seepw and that same is used in the pseudo static and pseudo dynamic analyses to make the approach more realistic. Pdf analysis of retaining wall in static and seismic. Preaccepted geotechnical programme list in ascending order of valid till. This approach is similar to the way gravity is introduced in the model but we can specify the magnitude and also the direction i. Evaluation of the pseudostatic analyses of earth dams using. Plaxis is used worldwide by top engineering companies and institutions in the civil and geotechnical engineering industry. However, these methods generally do not throw light on deformations of slope, which governs the serviceability of slopes after earthquakes. When using numerical modeling software such as plaxis 2d to model slope stability or a tall. A staged pseudo static analysis can be completed to give consideration to this scenario. Design and analysis of three different kinds of candles workflow geotechnical logical tunnel design threedimensional enter the options cad tool for calculating the structural forces of the volume of a cylinder, the size of the pile quasi static analysis define alpha coefficient. For geosynthetic reinforcement, it uses soilreinforcement interaction coefficients in combination with stress conditions at the slip surface to allow for bonding at the ends of the reinforcement. I have rarely use abaqus so can not tell much about that.
The effects of vibrations have to be calculated with a dynamic analysis when the frequency of the dynamic load is in the order or higher than the natural frequency of the medium. Low frequency vibrations can be calculated with a pseudo static analysis. With the dynamics module plaxis can analyse the effects of vibrations in the soil. Dynamic performance of the plaxis 2d model is validated with shake2000 by comparing siteresponse analysis results of both models. Slopew and plaxis are used for the limit equilibrium and fe methods, respectively. Plaxis 3d is a powerful and user friendly finite element package intended for threedimensional analysis of deformation and stability in geotechnical engineering and rock mechanics. The minimum values of factor of safety using pseudo static and pseudo dynamic method are obtained as 1. For dynamic analysis a calibrated plaxis 2d model of the reference case anchored sheet pile quay wall is created. A key feature of the software plaxis 3d foundation. I would like to apply a seismic coefficient to inertia such that lateral force is a fraction of g, and not an acceleration function similar to response spectra or time history. Newmarks sliding block analysis newmark, 1965 is the simplest method to calculate the permanent. By activating the pseudostatic option in a phase, and specifying the acceleration value in at least one of the components, these pseudo static accelerations will be activated in the. Finite element and finite difference modeling efforts have been applied to verify the seismic design methods in practice. Plaxis 3d dynamics module can handle more advanced seismic analysis than what is available by default in plaxis and can accurately calculate the effects of vibrations with a dynamics analysis when the frequency of the dynamic load is higher than the natural frequency of the medium.
256 167 416 1317 708 986 1059 1645 936 1206 612 811 512 1087 1211 1025 347 1444 819 1312 1400 831 1642 1127 898 1007 1677 1208 1156 359 1427 1262 545 253 975 1143 559 1360 701 860 763 60