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. Choose options for limit equilibrium or finite element stress methods, porewater pressures, trial slip surfaces, tension cracks, probabilistic and sensitivity methods, pseudostatic loading, partial factors, convergence criteria, and more. Abstractconventional seismic designs of quay walls in ports are mostly based on pseudostatic analysis. The static equilibrium of a continuum can be formulated as.
It is equipped with features to deal withvarious aspects of complex geotechnical structures and constructionprocesses using robust and theoretically sound computationalprocedures. In this paper, two drawbacks of the traditional pseudostatic method vertical slice method in the slope stability evaluation have been studied. Plaxis is used worldwide by top engineering companies and institutions in the civil and geotechnical engineering industry. Seismic analysis of reinforced earth wall along with soil structure. Pseudostatic lateral analysis technical knowledge base. 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.
Evaluation of the pseudostatic analyses of earth dams using fe. 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. I have rarely use abaqus so can not tell much about that. We do not pass your details to third parties to use. Prediction of the seismic behavior of an underground railway station. Performancebased seismic analysis of an anchored sheet. These results are in line with other studies that use added masses methods for hydrodynamic pressures. The seismic slope stability can be ascertained by evaluating factor of safety using pseudostatic or pseudodynamic approaches and force based equilibrium method.
Two options are available for calculating the undrained strengths prior to the application of the seismic forces. Fe plaxis analyses, the le mpm analyses may estimate 5 14% higher. 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. Pseudo static analysis was performed for the case study. The sequential seismic loading in the plaxis 2d model follows the same. Pdf pseudostatic and dynamic analyses of tunnels in trasversal. Improvement of pseudostatic method for slope stability.
Or, alternately one can use makdisi and seed 1978, which. A staged pseudostatic analysis involves the completion of two stability analyses for every single slip surface i. The results of the parametric analyses are reported in terms of pertinent normalized parameters, to provide a general framework for the assessment of wallsoil dynamic interaction under strong seismic excitation. That in turn raises the question of what seismic coefficient should be used in a pseudostatic analysis but a robust answer to that is provided in pyke 1991, which drew on the work of makdisi and seed 1978.
Plaxis program, however for more advanced seismic analysis the dynamics module is necessary. Researchers have also used the finiteelement method to analyze retaining systems and have developed computer software. It produces a scalar index of stability the factor of safety that is analogous to that produced by static stability analyses. Pseudostatic and dynamic nonlinear finite element analyses have been performed to assess the dynamic behaviour of gravity retaining walls subjected to horizontal earthquake loading. Between flac and plaxis, flac base on fdm analysis meanwhile plaxis base on fem analysis so they inheritance their parent properties. Slope stability evaluations by limit equilibrium and.
Plaxis 2d software accomplishes the analysis of retaining wall in static and seismic conditions. Pseudostatic stability analysis that uses a mechanism at a. This work is downloaded from delft university of technology. Fem is better for the static problem meanwhile the fdm. Prediction of the seismic behavior of an underground. The input procedures enable the enhanced output facilities provide a detailed. By activating the pseudostatic option in a phase, and specifying the acceleration value in at least one of the components, these pseudo static.
Plaxis 3d is a finite element pack for threedimensional analysis of deformation and stability in geotechnical engineering. Rational pseudostatic stability analysis of embankments. Plaxis software update archives page 2 of 5 plaxis. A numerical simulation on the dynamic response of mse wall. Model solutions for performancebased seismic analysis of an.
Evaluation of the pseudostatic analyses of earth dams. Lt is the transpose of a differential operator, defined as. In the output program the equivalent force arrow on your plots can now be hidden. Pseudo static acceleration and model size slope stability. It is equipped with features to deal with various aspects of complex geotechnical structures and construction processes using robust and theoretically sound computational procedures. Dynamic analyses were conducted to simulate the earthquakeinduced deformations of the dams using the computer program plaxis code. However, for more advanced seismic analysis, choose the plaxis 2d dynamics module. In this study plain strain numerical analysis is performed using plaxis dynamic program where prescribed displacement is applied at the bottom boundary of the. Plaxis 3d is a finite element package intendedfor threedimensional analysis of deformation and stability ingeotechnical engineering. Indeed, its similarity to the static limit equilibrium analyses routinely conducted by geotechnical engineers makes its computations easy to understand and perform.
The dynamics module of plaxis 2d allows us to perform dynamic analyses of the propagation of waves through the soil and their influence on structures. Shotcrete model vip rigid body tool with translation and rotation conditions applied from single arbitrary reference point. Rs3 3d finite element analysis for rock and soil software. 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. Slope stability evaluations by limit equilibrium and finite. The evaluation of seismic slope stability and ensuring serviceability of slope after earthquake is very important. Other wall displacements calculated using pseudostatic methods for other earthquakes are shown in fig. Pdf pseudostatic and dynamic analyses of tunnels in. Determination of stable cut and fill slopes assessment of overall stability. How to use command log files plaxis soilvision wiki. On the plaxis knowledge base support section, we have made command log files. For more information please look at our privacy statement. 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. Second, only peak ground acceleration pga is considered, and the effects of shaking.
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. I need to run a pseudostatic lateral analysis in which structural inertia represents the earthquake load. An example of the use of 3d slope stability analyses. In plaxis 2d and plaxis 3d a pseudo static acceleration can be defined per phase in the model conditions pseudostatic option in the. Downloading the slope64 program the source code for slope64 is written in fortran 2003, but users are provided with the executable file slope64.
Pdf analysis of retaining wall in static and seismic. Nevertheless, the straightforward pseudostatic analyses need a careful evaluation of the surface. 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. In the dynamic analysis, an actual measured earthquake acceleration time history has been scaled to provide peak ground acceleration values of 0. Pseudostatic and pseudodynamic calculations are applied to obtain the critical acceleration. In the pseudostatic analysis, the peak ground acceleration is converted into a pseudostatic inertia force and applied as a horizontal incremental gravity load. Plaxis 2d dynamics is an addon module to plaxis 2d. Multistage pseudostatic analysis geoslope international. When using numerical modeling software such as plaxis 2d to model slope stability or a tall. 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. Some important considerations in analysis of earthquakeinduced. Create a slopew analysis and set up the problem workspace. Gitirana 2017 multiplane slope stability analysis of tailings dams tailings and mine waste, banff, alberta. Comparison of the pseudostatic and dynamic behaviour of.
This example shows a building subjected to an earthquake and the usage of free vibration to determine the natural frequency. Traditionally, geotechnical engineers have assessed the seismic stability of slopes by pseudostatic analysis where the inertial force caused by. It uses pseudostatic analysis since the dynamic analysis cannot provide a safety calculation. Dynamic response of cantilever retaining walls considering.
Plaxis 3d is a finite element package intended for threedimensional analysis of deformation and stability in geotechnical engineering. Dynamic performance of the plaxis 2d model is validated with shake2000 by comparing siteresponse analysis results of both models. First, the sliding mass is divided into vertical slices according to this method, which is irrational to some extent in the seismic design of slope. Another important feature in sheet pile design is the assessment of the geotechnical overall stability. Delft university of technology model solutions for. The analysis is relatively simple and straightforward. Seismic analysis of reinforced earth wall along with soil. Tutorial examples or validation and verification cases. We will use this information to keep you updated about the products and services requested for administration and sales analysis. This update pack for plaxis 3d ae offers bug fixes and some improved functionality. From equation 6 and according to pseudostatic analysis, the base wall displacement 10. A staged pseudostatic analysis can be completed to give consideration to this scenario. Here are some key features of plaxis 3d foundation.
The pseudostatic analysis is the summation of a permanent body force representing the earthquake shaking with a static finite element analysis 16. However, the case slopes were found to have higher fos than the. Rs3 is a 3d finite element analysis program that can be used for a wide range of applications in both rock and soil, such as underground excavations, sequenced tunneling, surface excavations, slope stability, seepage analysis, consolidation analysis, and much more. 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. The first stage is completed without applying the seismic forces so that the effective stresses can be obtained at the base of each slice. 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. For dynamic analysis a calibrated plaxis 2d model of the reference case anchored sheet pile quay wall is created. Seismic displacement of gravity retaining walls kamal mohamed hafez ismail ibrahim. Comparison between numerical, pseudostatic and permissible sliding with vertical back surface.
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