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Analys av jord och konstruktion i samverkan - Utvärdering av olika FE-program

Jönsson, Daniel (2007)
Structural Mechanics
Civil Engineering (M.Sc.Eng.)
Abstract
When building below ground level in cities the regulations regarding deformations of surrounding soil are very strict. When using conventional methods of calculation it is difficult to predict the occurring deformations. This is why it has become more common to use FE-modeling to determine deformations. With FE-modelling it is possible to take the interactions between soil and construction into consideration.

There are FE-programs made for modelling constructions but it is difficult to model soil with these. In programs made for modelling geotechnical situations problems can arise with modelling structures in a satisfying way. The purpose of this work is to evaluate a few different programs for analysing the soil and structure... (More)
When building below ground level in cities the regulations regarding deformations of surrounding soil are very strict. When using conventional methods of calculation it is difficult to predict the occurring deformations. This is why it has become more common to use FE-modeling to determine deformations. With FE-modelling it is possible to take the interactions between soil and construction into consideration.

There are FE-programs made for modelling constructions but it is difficult to model soil with these. In programs made for modelling geotechnical situations problems can arise with modelling structures in a satisfying way. The purpose of this work is to evaluate a few different programs for analysing the soil and structure interaction. In this work ABAQUS, Plaxis and Z-Soil have been compared. ABAQUS is a general purpose program whereas Plaxis and Z-Soil were developed specially for geotechnical modelling.

In this work FE-modelling of two different cases has been performed. One simplefied case is used for lerning of how to use the program and it has also been used for comparison between computer aided calculations and conventional manual calculation. The second case is a part of the City-Tunnel project in Malmö where there was a fairly detailed investigation along with measurements of the displacement of the soil using inclinometers.

Modelling of projects like these with ABAQUS is complicated. Plaxis is very userfriendly and easy but it gives lesser options to the user. Z-Soil, on the other hand, is somewhat more difficult to learn how to use and it takes more time to prepare the model, but with the program the user gets more options.

The models in Plaxis and Z-Soil give relatively good accuracy in comparison with reality. In ABAQUS no modelling of the case from practice has been performed, but in the simplified case it shows that there is no major difference in the results between the different programs. The computed displacements are somewhat larger than the measured values. One reason for obtaining larger values in the simulations is that material data has been chosen with a safety margin when the geotechnical survey was performed. Another reason can be that ground water has already been pumped away from the outside of the diaphragm wall in reality but not in the model. (Less)
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author
Jönsson, Daniel
supervisor
organization
year
type
H3 - Professional qualifications (4 Years - )
subject
keywords
FE-modellering, Jord, Geoteknik, FEM, ABAQUS, Z-soil, Plaxis, Slitsmur, Sponter, Citytunneln
report number
TVSM-5145
ISSN
0281-6679
language
Swedish
id
3566836
date added to LUP
2013-08-05 11:50:41
date last changed
2013-10-07 12:02:21
@misc{3566836,
  abstract     = {When building below ground level in cities the regulations regarding deformations of surrounding soil are very strict. When using conventional methods of calculation it is difficult to predict the occurring deformations. This is why it has become more common to use FE-modeling to determine deformations. With FE-modelling it is possible to take the interactions between soil and construction into consideration. 
 
There are FE-programs made for modelling constructions but it is difficult to model soil with these. In programs made for modelling geotechnical situations problems can arise with modelling structures in a satisfying way. The purpose of this work is to evaluate a few different programs for analysing the soil and structure interaction. In this work ABAQUS, Plaxis and Z-Soil have been compared. ABAQUS is a general purpose program whereas Plaxis and Z-Soil were developed specially for geotechnical modelling.

In this work FE-modelling of two different cases has been performed. One simplefied case is used for lerning of how to use the program and it has also been used for comparison between computer aided calculations and conventional manual calculation. The second case is a part of the City-Tunnel project in Malmö where there was a fairly detailed investigation along with measurements of the displacement of the soil using inclinometers.

Modelling of projects like these with ABAQUS is complicated. Plaxis is very userfriendly and easy but it gives lesser options to the user. Z-Soil, on the other hand, is somewhat more difficult to learn how to use and it takes more time to prepare the model, but with the program the user gets more options.

The models in Plaxis and Z-Soil give relatively good accuracy in comparison with reality. In ABAQUS no modelling of the case from practice has been performed, but in the simplified case it shows that there is no major difference in the results between the different programs. The computed displacements are somewhat larger than the measured values. One reason for obtaining larger values in the simulations is that material data has been chosen with a safety margin when the geotechnical survey was performed. Another reason can be that ground water has already been pumped away from the outside of the diaphragm wall in reality but not in the model.},
  author       = {Jönsson, Daniel},
  issn         = {0281-6679},
  keyword      = {FE-modellering,Jord,Geoteknik,FEM,ABAQUS,Z-soil,Plaxis,Slitsmur,Sponter,Citytunneln},
  language     = {swe},
  note         = {Student Paper},
  title        = {Analys av jord och konstruktion i samverkan - Utvärdering av olika FE-program},
  year         = {2007},
}