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Why twisting angles are diverse in graphene Moir’e patterns? (2013)
Jiang, Jin-Wu ; Wang, Bing-Shen ; Rabczuk, Timon
Why twisting angles are diverse in graphene Moir’e patterns?
Wavelet packet system identification (2006)
Brehm, Maik ; Bucher, Christian
Wavelet packet system identification
Wavelet Analysis in Structural Health Monitoring and Damage Detection (2005)
Zabel, Volkmar ; Brehm, Maik
Wavelet Analysis in Structural Health Monitoring and Damage Detection
Wavelet analysis and frequency band decompositions (2006)
Markwardt, Klaus
Wavelet analysis and frequency band decompositions
Vibration-based detection of structural damage in a railway bridge - a comparitive study (2011)
Ahmad, Sofyan ; Zabel, Volkmar ; Brehm, Maik
Vibration-based detection of structural damage in a railway bridge - a comparitive study
Versuchstechniken zur Kennwertermittlung (2001)
Heuler, P. ; Vormwald, M.
Versuchstechniken zur Kennwertermittlung
Verformungsverhalten und rechnerische Abschätzung der Ermüdungslebensdauer metallischer Werkstoffe unter mehrachsig nichtproportionaler Beanspruchung (2002)
Döring, R. ; Hoffmeyer, J. ; Seeger, T. ; Vormwald, M.
Verformungsverhalten und rechnerische Abschätzung der Ermüdungslebensdauer metallischer Werkstoffe unter mehrachsig nichtproportionaler Beanspruchung
Verformungsverhalten und rechnerische Abschätzung der Ermüdungslebensdauer metallischer Werkstoffe unter mehrachsig nichtproportionaler Beanspruchung (2002)
Döring, R. ; Hoffmeyer, J. ; Seeger, T. ; Vormwald, M.
Verformungsverhalten und rechnerische Abschätzung der Ermüdungslebensdauer metallischer Werkstoffe unter mehrachsig nichtproportionaler Beanspruchung
Variance-based sensitivity analyses of piezoelectric models (2015)
Lahmer, Tom ; Ilg, J. ; Lerch, Reinhard
Variance-based sensitivity analyses of piezoelectric models
Untersuchungen zum Kurzrissfortschrittskonzept unter mehrachsig nichtproportionaler Beanspruchung" DVM-Bericht 683 des DFG-Kolloquiums (2000)
Döring, R. ; Hoffmeyer, J. ; Lengnick, M. ; Schmidt, K.H. ; Seeger, T. ; Vormwald, M.
Untersuchungen zum Kurzrissfortschrittskonzept unter mehrachsig nichtproportionaler Beanspruchung" DVM-Bericht 683 des DFG-Kolloquiums
Uncertainty quantification of dry woven fabrics: A sensitivity analysis on material properties (2014)
Ilyani Akmar, A.B. ; Lahmer, Tom ; Bordas, Stéphane Pierre Alain ; Beex, L.A.A. ; Rabczuk, Timon
Uncertainty quantification of dry woven fabrics: A sensitivity analysis on material properties
Uncertainty quantification for multiscale modeling of polymer nanocomposites with correlated parameters (2015)
Vu-Bac, N. ; Rafiee, Roham ; Zhuang, Xiaoying ; Lahmer, Tom ; Rabczuk, Timon
Uncertainty quantification for multiscale modeling of polymer nanocomposites with correlated parameters
Uncertainty analysis in multiscale modeling of concrete based on continuum micromechanics (2017)
Göbel, Luise ; Lahmer, Tom ; Osburg, Andrea
Uncertainty analysis in multiscale modeling of concrete based on continuum micromechanics
Uncertainties propagation in metamodel-based probabilistic optimization of CNT/polymer composite structure using stochastic multi-scale modeling (2014)
Ghasemi, Hamid ; Rafiee, Roham ; Zhuang, Xiaoying ; Muthu, Jacob ; Rabczuk, Timon
Uncertainties propagation in metamodel-based probabilistic optimization of CNT/polymer composite structure using stochastic multi-scale modeling
Topology optimization of piezoelectric nanostructures (2016)
Nanthakumar, S.S. ; Lahmer, Tom ; Zhuang, Xiaoying ; Park, Harold S. ; Rabczuk, Timon
Topology optimization of piezoelectric nanostructures
Thermo-hydro-mechanische 3-D-Simulation von Staumauern‐Modellierung und Validierung (2016)
Lahmer, Tom ; Nguyen-Tuan, Long ; Könke, Carsten ; Bettzieche, Volker
Thermo-hydro-mechanische 3-D-Simulation von Staumauern‐Modellierung und Validierung
The utilization of a visualisation tool in system identification (2000)
Zabel, Volkmar ; Bucher, Christian
The utilization of a visualisation tool in system identification
The tensile and shear failure behavior dependence on chain length and temperature in amorphous polymers (2015)
Zhao, Jiyun ; Lu, Lixin ; Rabczuk, Timon
The tensile and shear failure behavior dependence on chain length and temperature in amorphous polymers
The interface strength and debonding for composite structures: review and recent developments (2015)
Ben, S. ; Zhao, Jun-Hua ; Zhang, Yancheng ; Rabczuk, Timon
The interface strength and debonding for composite structures: review and recent developments
The influence of temperature varying material parameters on the dynamic behavior of short span railway bridges (2010)
Zabel, Volkmar ; Brehm, Maik ; Nikulla, Susanne
The influence of temperature varying material parameters on the dynamic behavior of short span railway bridges
The extended unsymmetric frontal solution for multiple-point constraints (2014)
Areias, Pedro ; Rabczuk, Timon ; Barbosa, J.I.
The extended unsymmetric frontal solution for multiple-point constraints
The dynamic behaviour of the `Erlebnisbrücke' on the BUGA in Ronneburg (2007)
Zabel, Volkmar ; Bleiziffer, J. ; Trabert, Josef
The dynamic behaviour of the `Erlebnisbrücke' on the BUGA in Ronneburg
The dynamic behaviour of a historical bell tower - in- situ tests and numerical investigations (2000)
Zabel, Volkmar ; Bucher, Christian ; Riedel, J.
The dynamic behaviour of a historical bell tower - in- situ tests and numerical investigations
The development of a damage tolerance concept for railway components and its demonstration for a railway axle (2005)
Zerbst, U. ; Vormwald, M. ; Andersch, C. ; Mädler, K. ; Pfuff, M.
The development of a damage tolerance concept for railway components and its demonstration for a railway axle
The application of the wavelet transformation in parametric system identification (2002)
Zabel, Volkmar
The application of the wavelet transformation in parametric system identification
Tension-induced phase transition of single-layer molybdenum disulphide (MoS2) at low temperatures (2014)
Zhao, Jun-Hua ; Kou, Liangzhi ; Jiang, Jin-Wu ; Rabczuk, Timon
Tension-induced phase transition of single-layer molybdenum disulphide (MoS2) at low temperatures
T-spline based XIGA for Fracture Analysis of Orthotropic Media (2015)
Ghorashi, Seyed Shahram ; Valizadeh, N. ; Mohammadi, S. ; Rabczuk, Timon
T-spline based XIGA for Fracture Analysis of Orthotropic Media
System identification of high-speed railway bridges (2008)
Zabel, Volkmar ; Brehm, Maik
System identification of high-speed railway bridges
System identification and damage detection of a prestressed concrete beam (2006)
Unger, Jörg F. ; Teughels, A. ; De Roeck, G.
System identification and damage detection of a prestressed concrete beam
Synthese und Analyse von gekoppelten Modellen im konstruktiven Ingenieurbau (2011)
Stein, Peter ; Lahmer, Tom ; Bock, Sebastian
Synthese und Analyse von gekoppelten Modellen im konstruktiven Ingenieurbau
Superior thermal conductivity and extremely high mechanical strength in polyethylene chains from ab initio calculation (2012)
Jiang, Jin-Wu ; Zhao, Jun-Hua ; Zhou, K. ; Rabczuk, Timon
The upper limit of the thermal conductivity and the mechanical strength are predicted for the polyethylene chain, by performing the ab initio calculation and applying the quantum mechanical non-equilibrium Green’s function approach. Specially, there are two main findings from our calculation: (1) the thermal conductivity can reach a high value of 310 Wm−1 K−1 in a 100 nm polyethylene chain at room temperature and the thermal conductivity increases with the length of the chain; (2) the Young’s modulus in the polyethylene chain is as high as 374.5 GPa, and the polyethylene chain can sustain 32.85%±0.05% (ultimate) strain before undergoing structural phase transition into gaseous ethylene.
Structural Reliability and Stochastic Finite Elements (2003)
Bucher, Christian
Structural Reliability and Stochastic Finite Elements
Stochastic simulation of cracking in concrete structures using multi-parameter random fields (2006)
Most, Thomas ; Bucher, Christian
Stochastic simulation of cracking in concrete structures using multi-parameter random fields
Stochastic predictions of interfacial characteristic of polymeric nanocomposites (PNCs) (2014)
Vu-Bac, N. ; Lahmer, Tom ; Zhang, Yancheng ; Zhuang, Xiaoying ; Rabczuk, Timon
Stochastic predictions of interfacial characteristic of polymeric nanocomposites (PNCs)
Stochastic predictions of bulk properties of amorphous polyethylene based on molecular dynamics simulations (2014)
Vu-Bac, N. ; Lahmer, Tom ; Keitel, Holger ; Zhao, Jun-Hua ; Zhuang, Xiaoying ; Rabczuk, Timon
Stochastic predictions of bulk properties of amorphous polyethylene based on molecular dynamics simulations
Stochastic modeling of cohesive crack propagation using meshless discretization techniques (2004)
Most, Thomas ; Unger, Jörg F. ; Bucher, Christian
Stochastic modeling of cohesive crack propagation using meshless discretization techniques
Stochastic modeling of cohesive crack evolution in concrete using meshless interpolation techniques (2004)
Most, Thomas ; Bucher, Christian
Stochastic modeling of cohesive crack evolution in concrete using meshless interpolation techniques
Stochastic model updating using perturbation methods in combination with neural network estimations (2009)
Brehm, Maik ; Zabel, Volkmar ; Unger, Jörg F.
Stochastic model updating using perturbation methods in combination with neural network estimations
Stochastic Model Updating methods - a comparitive study (2009)
Zabel, Volkmar ; Brehm, Maik
Stochastic Model Updating methods - a comparitive study
Stochastic finite element modeling of damage evolutions of R/C beams (2001)
Ebert, Matthias ; Bucher, Christian
Stochastic finite element modeling of damage evolutions of R/C beams
Stochastic dynamic stability analysis of shell structures (2005)
Most, Thomas ; Bucher, Christian
Stochastic dynamic stability analysis of shell structures
Stochastic dynamic stability analysis for nonlinear structures (2002)
Most, Thomas ; Bucher, Christian
Stochastic dynamic stability analysis for nonlinear structures
Stochastic crack growth simulation in R/C structures by means of meshless methods (2005)
Most, Thomas ; Unger, Jörg F. ; Bucher, Christian
Stochastic crack growth simulation in R/C structures by means of meshless methods
Statistical extraction of process zones and representative subspaces in fracture of random composites (2013)
Kerfriden, Pierre ; Schmidt, K.M. ; Rabczuk, Timon ; Bordas, Stéphane Pierre Alain
Statistical extraction of process zones and representative subspaces in fracture of random composites
Static, free vibration and buckling analysis of laminated composite Reissner-Mindlin plates using NURBS-based isogeometric approach (2012)
Thai, Chien H. ; Nguyen-Xuan, Hung ; Nguyen-Thanh, Nhon ; Le, T.H. ; Nguyen-Thoi, T. ; Rabczuk, Timon
This paper presents a novel numerical procedure based on the framework of isogeometric analysis for static, free vibration, and buckling analysis of laminated composite plates using the first-order shear deformation theory. The isogeometric approach utilizes non-uniform rational B-splines to implement for the quadratic, cubic, and quartic elements. Shear locking problem still exists in the stiffness formulation, and hence, it can be significantly alleviated by a stabilization technique. Several numerical examples are presented to show the performance of the method, and the results obtained are compared with other available ones.
Stability analysis for randomly imperfect structures (2000)
Schorling, York ; Bucher, Christian ; Purkert, G.
Stability analysis for randomly imperfect structures
Stability Analysis for Imperfect Systems with Random Loading (2001)
Schorling, York ; Most, Thomas ; Bucher, Christian
Stability Analysis for Imperfect Systems with Random Loading
Spatial and temporal multiscale simulations of damage processes for concrete (2006)
Könke, Carsten ; Eckardt, Stefan ; Häfner, Stefan
Spatial and temporal multiscale simulations of damage processes for concrete
Size-Sensitive Young’s Modulus of Kinked Silicon Nanowires (2013)
Jiang, Jin-Wu ; Zhao, Jun-Hua ; Rabczuk, Timon
We perform both classical molecular dynamics simulations and beam model calculations to investigate the Young's modulus of kinked silicon nanowires (KSiNWs). The Young's modulus is found to be highly sensitive to the arm length of the kink and is essentially inversely proportional to the arm length. The mechanism underlying the size dependence is found to be the interplay between the kink angle potential and the arm length potential, where we obtain an analytic relationship between the Young's modulus and the arm length of the KSiNW. Our results provide insight into the application of this novel building block in nanomechanical devices.
Size dependent free flexural vibration behavior of functionally graded nanoplates (2012)
Natarajan, S. ; Chakraborty, S. ; Thangavel, M. ; Bordas, Stéphane Pierre Alain ; Rabczuk, Timon
Size dependent free flexural vibration behavior of functionally graded nanoplates
Simulation of the fracture behaviour of concrete using continuum damage models at the mesoscale (2004)
Eckardt, Stefan ; Häfner, Stefan ; Könke, Carsten
Simulation of the fracture behaviour of concrete using continuum damage models at the mesoscale
Simulation of concrete using the extended finite element method (2006)
Unger, Jörg F. ; Könke, Carsten
Simulation of concrete using the extended finite element method
Short Fatigue Crack Growth Model under Multiaxial Nonproportional Loading (2001)
Hoffmeyer, J. ; Döring, R. ; Seeger, T. ; Vormwald, M.
Short Fatigue Crack Growth Model under Multiaxial Nonproportional Loading
SFE- Modelling of dynamic and static properties of R/C Beams in progressive damage (2000)
Ebert, Matthias ; Bucher, Christian
SFE- Modelling of dynamic and static properties of R/C Beams in progressive damage
Sequential reliability based optimization of fiber content and dispersion in fiber reinforced composite by using NURBS finite elements (2014)
Ghasemi, Hamid ; Brighenti, Roberto ; Zhuang, Xiaoying ; Muthu, Jacob ; Rabczuk, Timon
Sequential reliability based optimization of fiber content and dispersion in fiber reinforced composite by using NURBS finite elements
Seismic analysis of structural response using simplified soil-structure interaction models (2010)
Nasser, Mourad ; Schwedler, Michael ; Wuttke, Frank ; Könke, Carsten
Seismic analysis of structural response using simplified soil-structure interaction models
Schädigungs- und Verbundmodellierung für Stahlbetontragwerke (2005)
Könke, Carsten ; Eckardt, Stefan ; Häfner, Stefan ; Luther, Torsten ; Unger, Jörg F.
Schädigungs- und Verbundmodellierung für Stahlbetontragwerke
Schwingfestigkeitsanalyse und Lebensdauerermittlung geschweißter mehrachsig belasteter Komponenten von Nutzfahrzeugen (2000)
Savaidis, G. ; Feitzelmayer, K. ; Schliebner, R. ; Purkert, G. ; Vormwald, M.
Schwingfestigkeitsanalyse und Lebensdauerermittlung geschweißter mehrachsig belasteter Komponenten von Nutzfahrzeugen
Rotation free isogeometric thin shell analysis using PHT-splines (2011)
Nguyen-Thanh, Nhon ; Kiendl, J. ; Nguyen-Xuan, Hung ; Wüchner, R. ; Bletzinger, Kai-Uwe ; Bazilevs, Yuri ; Rabczuk, Timon
Rotation free isogeometric thin shell analysis using PHT-splines
Rissentstehung und Kurzrisswachstum unter Schwingbelastung (2002)
Vormwald, M.
Rissentstehung und Kurzrisswachstum unter Schwingbelastung
Risk assessment for damage tolerant structures (2005)
Könke, Carsten ; Petryna, Y. ; Singh, Ripudaman
Risk assessment for damage tolerant structures
Residual stress fields and fatigue analysis of autofrettaged parts (2002)
Thumser, Rayk ; Bergmann, Joachim W. ; Vormwald, M.
Residual stress fields and fatigue analysis of autofrettaged parts
Rational Framework for Probability of Collapse in Buildings (2014)
Hatahet, Tareq ; Könke, Carsten
Rational Framework for Probability of Collapse in Buildings
Quasicontinuum-based multiscale approaches for plate-like beam lattices experiencing in-plane and out-of-plane deformation (2014)
Beex, L.A.A. ; Kerfriden, Pierre ; Rabczuk, Timon ; Bordas, Stéphane Pierre Alain
Quasicontinuum-based multiscale approaches for plate-like beam lattices experiencing in-plane and out-of-plane deformation
Quasi-analytical solution for the stable system of the multi-layer folded graphene wrinkles (2013)
Zhang, Yancheng ; Wei, Ning ; Zhao, Jun-Hua ; Gong, Yadong ; Rabczuk, Timon
Quasi-analytical solution for the stable system of the multi-layer folded graphene wrinkles
Probabilistic analysis of concrete cracking using neural networks and random fields (2007)
Most, Thomas ; Bucher, Christian
Probabilistic analysis of concrete cracking using neural networks and random fields
Predicting The Fracture Toughness of PNCs: A Stochastic Approach Based on ANN and ANFIS (2015)
Hamdia, K. ; Lahmer, Tom ; Nguyen-Thoi, T. ; Rabczuk, Timon
Predicting The Fracture Toughness of PNCs: A Stochastic Approach Based on ANN and ANFIS
Polyhedral response surfaces for structural reliability assessment (2000)
Roos, Dirk ; Bucher, Christian ; Bayer, Veit
Polyhedral response surfaces for structural reliability assessment
Polycrystal models for the analysis of intergranular crack growth in metallic materials (2009)
Luther, Torsten ; Könke, Carsten
Polycrystal models for the analysis of intergranular crack growth in metallic materials
Phonon modes in single-walled molybdenum disulphide nanotubes: lattice dynamics calculation and molecular dynamics simulation (2014)
Jiang, Jin-Wu ; Wang, Bing-Shen ; Rabczuk, Timon
Phonon modes in single-walled molybdenum disulphide nanotubes: lattice dynamics calculation and molecular dynamics simulation
Phase-field modeling of fracture in linear thin shells (2014)
Amiri, Fatemeh ; Millán, D. ; Shen, Y. ; Rabczuk, Timon ; Arroyo, M.
Phase-field modeling of fracture in linear thin shells
Phase field modelling of stressed grain growth: Analytical study and the effect of microstructural length scale (2014)
Jamshidian, M. ; Rabczuk, Timon
Phase field modelling of stressed grain growth: Analytical study and the effect of microstructural length scale
Phantom-node method for shell models with arbitrary cracks (2012)
Chau-Dinh, T. ; Zi, Goangseup ; Lee, P.S. ; Song, Jeong-Hoon ; Rabczuk, Timon
A phantom-node method is developed for three-node shell elements to describe cracks. This method can treat arbitrary cracks independently of the mesh. The crack may cut elements completely or partially. Elements are overlapped on the position of the crack, and they are partially integrated to implement the discontinuous displacement across the crack. To consider the element containing a crack tip, a new kinematical relation between the overlapped elements is developed. There is no enrichment function for the discontinuous displacement field. Several numerical examples are presented to illustrate the proposed method.
PDE based determination of piezoelectric material tensors (2006)
Kaltenbacher, Barbara ; Lahmer, Tom ; Mohr, Marcus ; Kaltenbacher, Manfred
PDE based determination of piezoelectric material tensors.
Parametric system identification by means of the wavelet transformation (2002)
Zabel, Volkmar ; Bucher, Christian
Parametric system identification by means of the wavelet transformation
Parameteridentifikation mit Hilfe der schnellen Wavelet-Transformation (2002)
Markwardt, Klaus
Parameteridentifikation mit Hilfe der schnellen Wavelet-Transformation
Optimum fiber content and distribution in fiber-reinforced solids using a reliability and NURBS based sequential optimization approach (2015)
Ghasemi, Hamid ; Brighenti, Roberto ; Zhuang, Xiaoying ; Muthu, Jacob ; Rabczuk, Timon
Optimum _ber content and distribution in _ber-reinforced solids using a reliability and NURBS based sequential optimization approach
Optimizing maintenance interventions for deteriorating structures using cost-benefit criteria (2007)
Macke, M. ; Higuchi, Shoko
Optimizing maintenance interventions for deteriorating structures using cost-benefit criteria
Optimization of lifetime maintenance strategies for deteriorting structures considering probabilities of violating safety, condition, and cost thresholds (2006)
Bucher, Christian ; Frangopol, D.M.
Optimization of lifetime maintenance strategies for deteriorting structures considering probabilities of violating safety, condition, and cost thresholds
Optimization of fiber distribution in fiber reinforced composite by using NURBS functions (2014)
Ghasemi, Hamid ; Brighenti, Roberto ; Zhuang, Xiaoying ; Muthu, Jacob ; Rabczuk, Timon
Optimization of fiber distribution in fiber reinforced composite by using NURBS functions
Optimization of Elastic Properties and Weaving Patterns of Woven Composites (2013)
Bakar, I. ; Kramer, O. ; Bordas, Stéphane Pierre Alain ; Rabczuk, Timon
Optimization of Elastic Properties and Weaving Patterns of Woven Composites
Optimization of Centrifugal Compressor Impellers by a Multi-fidelity Sampling Method Taking Analytical and Empirical Information into Account (2019)
Schemmann, Christoph
Turbomachinery plays an important role in many cases of energy generation or conversion. Therefore, turbomachinery is a promising approaching point for optimization in order to increase the efficiency of energy use. In recent years, the use of automated optimization strategies in combination with numerical simulation has become increasingly popular in many fields of engineering. The complex interactions between fluid and solid mechanics encountered in turbomachines on the one hand and the high computational expense needed to calculate the performance on the other hand, have, however, prevented a widespread use of these techniques in this field of engineering. The objective of this work was the development of a strategy for efficient metamodel based optimization of centrifugal compressor impellers. In this context, the main focus is the reduction of the required numerical expense. The central idea followed in this research was the incorporation of preliminary information acquired from low-fidelity computation methods and empirical correlations into the sampling process to identify promising regions of the parameter space. This information was then used to concentrate the numerically expensive high-fidelity computations of the fluid dynamic and structure mechanic performance of the impeller in these regions while still maintaining a good coverage of the whole parameter space. The development of the optimization strategy can be divided into three main tasks. Firstly, the available preliminary information had to be researched and rated. This research identified loss models based on one dimensional flow physics and empirical correlations as the best suited method to predict the aerodynamic performance. The loss models were calibrated using available performance data to obtain a high prediction quality. As no sufficiently exact models for the prediction of the mechanical loading of the impellercould be identified, a metamodel based on finite element computations was chosen for this estimation. The second task was the development of a sampling method which concentrates samples in regions of the parameter space where high quality designs are predicted by the preliminary information while maintaining a good overall coverage. As available methods like rejection sampling or Markov-chain Monte-Carlo methods did not meet the requirements in terms of sample distribution and input correlation, a new multi-fidelity sampling method called “Filtered Sampling“has been developed. The last task was the development of an automated computational workflow. This workflow encompasses geometry parametrization, geometry generation, grid generation and computation of the aerodynamic performance and the structure mechanic loading. Special emphasis was put into the development of a geometry parametrization strategy based on fluid mechanic considerations to prevent the generation of physically inexpedient designs. Finally, the optimization strategy, which utilizes the previously developed tools, was successfully employed to carry out three optimization tasks. The efficiency of the method was proven by the first and second testcase where an existing compressor design was optimized by the presented method. The results were comparable to optimizations which did not take preliminary information into account, while the required computational expense cloud be halved. In the third testcase, the method was applied to generate a new impeller design. In contrast to the previous examples, this optimization featuredlargervariationsoftheimpellerdesigns. Therefore, theapplicability of the method to parameter spaces with significantly varying designs could be proven, too.
Optimale Positionierung von Messeinrichtungen an Staumauern zur Bauwerksüberwachung (2010)
Lahmer, Tom ; Könke, Carsten ; Bettzieche, Volker
Optimale Positionierung von Messeinrichtungen an Staumauern zur Bauwerksüberwachung
Optimal reference sensor positions for applications in model updating using output-only vibration test data based on random excitation: Part 2 - improved search strategy and experimental case study (2011)
Brehm, Maik ; Zabel, Volkmar ; Bucher, Christian
Optimal reference sensor positions for applications in model updating using output-only vibration test data based on random excitation: Part 2 - improved search strategy and experimental case study
Optimal reference sensor placement within roving setup configurations (2011)
Brehm, Maik ; Zabel, Volkmar ; Bucher, Christian
Optimal reference sensor placement within roving setup configurations
Optimal positioning of sensors for the monitoring of water dams (2010)
Lahmer, Tom ; Könke, Carsten ; Bettzieche, Volker
Optimal positioning of sensors for the monitoring of water dams
Optimal measurement selection for piezoelectric material tensor identification (2008)
Lahmer, Tom ; Kaltenbacher, Barbara ; Schulz, V.
Optimal measurement selection for piezoelectric material tensor identification.
Optimal experimental design for nonlinear ill-posed problems applied to gravity dams (2011)
Lahmer, Tom
Optimal experimental design for nonlinear ill-posed problems applied to gravity dams
On the numerical stability and mass-lumping schemes for explicit enriched meshfree methods (2012)
Talebi, Hossein ; Samaniego, C. ; Samaniego, Esteban ; Rabczuk, Timon
Meshfree methods (MMs) such as the element free Galerkin (EFG)method have gained popularity because of some advantages over other numerical methods such as the finite element method (FEM). A group of problems that have attracted a great deal of attention from the EFG method community includes the treatment of large deformations and dealing with strong discontinuities such as cracks. One efficient solution to model cracks is adding special enrichment functions to the standard shape functions such as extended FEM, within the FEM context, and the cracking particles method, based on EFG method. It is well known that explicit time integration in dynamic applications is conditionally stable. Furthermore, in enriched methods, the critical time step may tend to very small values leading to computationally expensive simulations. In this work, we study the stability of enriched MMs and propose two mass-lumping strategies. Then we show that the critical time step for enriched MMs based on lumped mass matrices is of the same order as the critical time step of MMs without enrichment. Moreover, we show that, in contrast to extended FEM, even with a consistent mass matrix, the critical time step does not vanish even when the crack directly crosses a node.
On the coupling of a commercial finite element package with lammps for multiscale modeling of materials (2013)
Silani, Mohammad ; Talebi, Hossein ; Arnold, Daniel ; Ziaei-Rad, S. ; Rabczuk, Timon
On the coupling of a commercial finite element package with lammps for multiscale modeling of materials
On model updating of existing structures utilizing measured dynamic responses (2005)
Bucher, Christian ; Pham, Hoang Anh
On model updating of existing structures utilizing measured dynamic responses
NURBS-based finite element analysis of functionally graded plates: static bending, vibration, buckling and flutter (2013)
Valizadeh, N. ; Natarajan, S. ; Gonzalez-Estrada, O.A. ; Rabczuk, Timon ; Tinh Quoc, Bui ; Bordas, Stéphane Pierre Alain
NURBS-based finite element analysis of functionally graded plates: static bending, vibration, buckling and flutter
Numerical Solution of the First-Passage Problem by FORM and Importance Sampling (2002)
Bucher, Christian
Numerical Solution of the First-Passage Problem by FORM and Importance Sampling
Numerical simulation techniques to study the structural response of the human chest following median sternotomy (2005)
Bruhin, R. ; Stock, U.A. ; Drücker, J.-P. ; Azhari, T. ; Wippermann, J. ; Albes, J.M. ; Hintze, D. ; Eckardt, Stefan ; Könke, Carsten ; Wahlers, T.
Numerical simulation techniques to study the structural response of the human chest following median sternotomy
Numerical Simulation of Thermo-Chemo-Hygro-Mechanical Alkali-Silica Reaction Model in Concrete at the Mesoscale and Macroscale (2014)
Itam, Zarina
Alkali-silica reaction causes major problems in concrete structures due to the rapidity of its deformation which leads to the serviceability limit of the structure being reached well before its time. Factors that affect ASR vary greatly, including alkali and silica content, relative humidity, temperature and porosity of the cementitious matrix,all these making it a very complex phenomenon to consider explicitly. With this in mind, the finite element technique was used to build models and generate expansive pressures and damage propagation due to ASR under the influence of thermo-hygrochemoelastic loading. Since ASR initializes in the mesoscopic regions of the concrete, the accumulative effects of its expansion escalates onto the macroscale level with the development of web cracking on the concrete surface, hence solution of the damage model as well as simulation of the ASR phenomenon at both the macroscale and mesoscale levels have been performed. The macroscale model realizes the effects of ASR expansion as a whole and shows how it develops under the influence of moisture, thermal and mechanical loading. Results of the macroscale modeling are smeared throughout the structure and are sufficient to show how damage due to ASR expansion orientates. As opposed to the mesoscale model, the heterogeneity of the model shows us how difference in material properties between aggregates and the cementitious matrix facilitates ASR expansion. With both these models, the ASR phenomenon under influence of thermo-chemo-hygro-mechanical loading can be better understood.
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