Examples of Problem Solved

List of real engineering problems solved with help of SIFEL package follows.

Hydro-thermo-mechanical analysis of reactor vessel

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3D coupled hydro-thermo analysis and 2D coupled hydro-thermo-mechanical analysis of reactor vessel performed within the European project MAECENAS. The project dealt with prolongation of service life of nuclear power plants in and it was also supported by British Energy company. The analysis represents section of reactor vessel which have been mounted in nuclear power plant in Hinkley.

Thermo-mechanical analysis of containment

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3D coupled thermo-mechanical analysis of prestressed concrete containment in Temelín. The simulation was carried out for 50 years of operation with help of creep B3 model and orthotropic damage model. Parallel version of METR was used in order to reduce computational time. The mesh was decomposed into 8 domains.

Eigenvibration of highway bridges in Lahovice (Prague)

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Highway bridges are subjected to experimental analysis of their vibration before they are put into service. In order to perform the experiments smoothly and as much precisely as possible, it is useful to determine the eigenfrequencies and eigenmodes by numerical analysis in advance. Sensors should be located in antinodes because of significant displacements which can be measured more precisely than small displacements near the vibration nodes. The bridges analysed are highway concrete prestressed bridges in Prague. They are six-span structures made from the prestressed concrete C35/45-XF2+XD1. The length of the left bridge is 560.976 m while the right bridge has the length 551.540 m. Both bridges are horizontally curved with radius 747.5 m and 753.75 m for the left and right bridge, respectively.

Analysis of foundation slabs

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Computer simulation of a foundation concrete slab behaviour in an early stage. The Künzel and Kiessl`s model was used to analyze heat and moisture fields and was extended by a set of climatic conditions and by a model of hydration heat evolution in concrete. The isotropic damage model was used together with the B3 model for description of concrete mechanical behaviour. The code was extended by the implementation of the gradual construction process using time controlled switching on/off of particular degrees of freedom and elements.

Simulation of construction of prestressed concrete highway bridge

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The master thesis dealing with the modelling of gradual construction of road bridge and its creep. The bridge is constructed with the help of the shifting falsework. Two technologies of gradual construction are studied. The shifting falsework is supported either by bridge piers (columns) or by cast cantilever from the previous phase and by the following piers. There are three numerical models of the bridge in this thesis. The first model assumes the whole bridge without gradual construction (version 3). The bridge is cast at one time instant and the prestress is applied all at once. Second numerical model describes gradual construction, where the shifting falsework is supported by piers (version 1). Third numerical model describes gradual construction, where the shifting falsework is supported by previously cast cantilever and the following pier (version 2). Computations were carried out module MEFEL where the creep was described by the Bazant model B3.

Analysis of rock cliff stability in Chotek road (Prague)

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Nonlinear analysis of rock cliff stability with help of Mohr-Coulomb material model. Except of gravity, the rock cliff is loaded by elevated road and in some sections, there is a cutoff due to hotel building placed under the cliff. The input files in referred below contains 3D nonlinear analysis of the section No. 10.

Description of heat hydration by the CEMHYD model

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Analysis of heat transport across the bridge cross section with help of CemHyd3D model.

Earthquake simulation

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Simulation of behavior of high buildings in earthquake.

Multi-scale coupled heat and moisture transport in Charles bridge, Prague

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A fully coupled transient heat and moisture transport in a masonry structure was examined in in this case. Supported by several successful applications in civil engineering the nonlinear diffusion model proposed by Künzel was adopted in this study. A strong material heterogeneity together with a significant dependence of the model parameters on initial conditions as well as the gradients of heat and moisture fields indicates the use of a hierarchical modeling strategy to solve the problem of this kind. Attention is limited to the classical first order homogenization in a spatial domain developed here in the framework of a two step (meso-macro) multi-scale computational scheme (FE problem). A two-dimensional section of Charles Bridge subjected to actual climatic conditions is analyzed with help of FE scheme for the parallel computing.

Analysis of Bridge in city of Mělník

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The bridge analysed is road box girder prestressed concrete bridge. The lengths of spans are 59, 104 and 59 m. The width of bridge deck is 13.4 m. The height of the box girder varies from 2.015 to 5.8 m. The thickness of walls of box girder varies from 540 to 1,100 mm, thickness of plates varies from 200 to 1,200 mm. The thickness of walls is not continuous. There are jumps in every span.

Parallel 3D Hygro-thermo-mechanical analysis of Charles bridge in Prague

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The numerical model simulates the coupled heat and moisture transfer and mechanical response of one half of arch III in the course of two years, 2011 - 2012. The finite element mesh was created using tetrahedron elements with linear approximation functions. It has 73749 nodes and 387773 elements. The analyzed segment taken out of Charles Bridge was split into 12 sub-domains. The average number of nodes and elements on one sub-domain is 7000 and 32000, respectively. Parallel computation was performed on a heterogeneous PC cluster where computers are based on the 32 bit Intel E6850 processors with a different frequency in the range of 2.4 to 3 GHz and the memory from 3GB to 3.3 GB. The parallel algorithm performed 7596 time steps. A time step was set to cover two hours (7200 seconds). The overall consumption of the computation (CPU) time was one month.


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