TY - JOUR A1 - Yang, Shih-Wei A1 - Budarapu, Pattabhi Ramaiah A1 - Mahapatra, D.R. A1 - Bordas, Stéphane Pierre Alain A1 - Zi, Goangseup A1 - Rabczuk, Timon T1 - A Meshless Adaptive Multiscale Method for Fracture JF - Computational Materials Science N2 - A Meshless Adaptive Multiscale Method for Fracture KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 382 EP - 395 ER - TY - JOUR A1 - Jia, Yue A1 - Zhang, Yongjie A1 - Rabczuk, Timon T1 - A Novel Dynamic Multilevel Technique for Image Registration JF - Computers and Mathematics with Applications N2 - A Novel Dynamic Multilevel Technique for Image Registration KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 ER - TY - JOUR A1 - Areias, Pedro A1 - Rabczuk, Timon A1 - Cesar de Sa, J.M. A1 - Jorge, R.N. T1 - A semi-implicit _nite strain shell algorithm using in-plane strains based on least-squares JF - Computational Mechanics N2 - A semi-implicit _nite strain shell algorithm using in-plane strains based on least-squares KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 ER - TY - JOUR A1 - Jiang, Jin-Wu A1 - Rabczuk, Timon A1 - Park, Harold S. T1 - A Stillinger-Weber Potential for Single-Layer Black Phosphorus, and the Importance of Cross-Pucker Interactions for Negative Poisson's Ratio and Edge Stress-Induced Bending JF - Nanoscale N2 - The distinguishing structural feature of single-layered black phosphorus is its puckered structure, which leads to many novel physical properties. In this work, we first present a new parameterization of the Stillinger–Weber potential for single-layered black phosphorus. In doing so, we reveal the importance of a cross-pucker interaction term in capturing its unique mechanical properties, such as a negative Poisson's ratio. In particular, we show that the cross-pucker interaction enables the pucker to act as a re-entrant hinge, which expands in the lateral direction when it is stretched in the longitudinal direction. As a consequence, single-layered black phosphorus has a negative Poisson's ratio in the direction perpendicular to the atomic plane. As an additional demonstration of the impact of the cross-pucker interaction, we show that it is also the key factor that enables capturing the edge stress-induced bending of single-layered black phosphorus that has been reported in ab initio calculations. KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 U6 - http://dx.doi.org/10.1039/C4NR07341J ER - TY - JOUR A1 - Silani, Mohammad A1 - Talebi, Hossein A1 - Ziaei-Rad, S. A1 - Hamouda, A.M.S. A1 - Zi, Goangseup A1 - Rabczuk, Timon T1 - A three dimensional Extended Arlequin Method for Dynamic Fracture JF - Computational Materials Science N2 - A three dimensional Extended Arlequin Method for Dynamic Fracture KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 425 EP - 431 ER - TY - JOUR A1 - Vu-Bac, N. A1 - Silani, Mohammad A1 - Lahmer, Tom A1 - Zhuang, Xiaoying A1 - Rabczuk, Timon T1 - A unified framework for stochastic predictions of Young's modulus of clay/epoxy nanocomposites (PCNs) JF - Computational Materials Science N2 - A unified framework for stochastic predictions of Young's modulus of clay/epoxy nanocomposites (PCNs) KW - Angewandte Mathematik KW - Stochastik KW - Strukturmechanik Y1 - 2015 SP - 520 EP - 535 ER - TY - JOUR A1 - Msekh, Mohammed Abdulrazzak A1 - Sargado, M. A1 - Jamshidian, M. A1 - Areias, Pedro A1 - Rabczuk, Timon T1 - ABAQUS implementation of phase_field model for brittle fracture JF - Computational Materials Science N2 - ABAQUS implementation of phase_field model for brittle fracture KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 472 EP - 484 ER - TY - THES A1 - Budarapu, Pattabhi Ramaiah T1 - Adaptive multiscale methods for fracture T1 - Adaptive Multiskalen-Methoden zur Modellierung von Materialversagen N2 - One major research focus in the Material Science and Engineering Community in the past decade has been to obtain a more fundamental understanding on the phenomenon 'material failure'. Such an understanding is critical for engineers and scientists developing new materials with higher strength and toughness, developing robust designs against failure, or for those concerned with an accurate estimate of a component's design life. Defects like cracks and dislocations evolve at nano scales and influence the macroscopic properties such as strength, toughness and ductility of a material. In engineering applications, the global response of the system is often governed by the behaviour at the smaller length scales. Hence, the sub-scale behaviour must be computed accurately for good predictions of the full scale behaviour. Molecular Dynamics (MD) simulations promise to reveal the fundamental mechanics of material failure by modeling the atom to atom interactions. Since the atomistic dimensions are of the order of Angstroms ( A), approximately 85 billion atoms are required to model a 1 micro- m^3 volume of Copper. Therefore, pure atomistic models are prohibitively expensive with everyday engineering computations involving macroscopic cracks and shear bands, which are much larger than the atomistic length and time scales. To reduce the computational effort, multiscale methods are required, which are able to couple a continuum description of the structure with an atomistic description. In such paradigms, cracks and dislocations are explicitly modeled at the atomistic scale, whilst a self-consistent continuum model elsewhere. Many multiscale methods for fracture are developed for "fictitious" materials based on "simple" potentials such as the Lennard-Jones potential. Moreover, multiscale methods for evolving cracks are rare. Efficient methods to coarse grain the fine scale defects are missing. However, the existing multiscale methods for fracture do not adaptively adjust the fine scale domain as the crack propagates. Most methods, therefore only "enlarge" the fine scale domain and therefore drastically increase computational cost. Adaptive adjustment requires the fine scale domain to be refined and coarsened. One of the major difficulties in multiscale methods for fracture is to up-scale fracture related material information from the fine scale to the coarse scale, in particular for complex crack problems. Most of the existing approaches therefore were applied to examples with comparatively few macroscopic cracks. Key contributions The bridging scale method is enhanced using the phantom node method so that cracks can be modeled at the coarse scale. To ensure self-consistency in the bulk, a virtual atom cluster is devised providing the response of the intact material at the coarse scale. A molecular statics model is employed in the fine scale where crack propagation is modeled by naturally breaking the bonds. The fine scale and coarse scale models are coupled by enforcing the displacement boundary conditions on the ghost atoms. An energy criterion is used to detect the crack tip location. Adaptive refinement and coarsening schemes are developed and implemented during the crack propagation. The results were observed to be in excellent agreement with the pure atomistic simulations. The developed multiscale method is one of the first adaptive multiscale method for fracture. A robust and simple three dimensional coarse graining technique to convert a given atomistic region into an equivalent coarse region, in the context of multiscale fracture has been developed. The developed method is the first of its kind. The developed coarse graining technique can be applied to identify and upscale the defects like: cracks, dislocations and shear bands. The current method has been applied to estimate the equivalent coarse scale models of several complex fracture patterns arrived from the pure atomistic simulations. The upscaled fracture pattern agree well with the actual fracture pattern. The error in the potential energy of the pure atomistic and the coarse grained model was observed to be acceptable. A first novel meshless adaptive multiscale method for fracture has been developed. The phantom node method is replaced by a meshless differential reproducing kernel particle method. The differential reproducing kernel particle method is comparatively more expensive but allows for a more "natural" coupling between the two scales due to the meshless interpolation functions. The higher order continuity is also beneficial. The centro symmetry parameter is used to detect the crack tip location. The developed multiscale method is employed to study the complex crack propagation. Results based on the meshless adaptive multiscale method were observed to be in excellent agreement with the pure atomistic simulations. The developed multiscale methods are applied to study the fracture in practical materials like Graphene and Graphene on Silicon surface. The bond stretching and the bond reorientation were observed to be the net mechanisms of the crack growth in Graphene. The influence of time step on the crack propagation was studied using two different time steps. Pure atomistic simulations of fracture in Graphene on Silicon surface are presented. Details of the three dimensional multiscale method to study the fracture in Graphene on Silicon surface are discussed. T3 - ISM-Bericht // Institut für Strukturmechanik, Bauhaus-Universität Weimar - 2015,1 KW - Material KW - Strukturmechanik KW - Materialversagen KW - material failure Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20150507-23918 ER - TY - JOUR A1 - Nguyen-Thanh, Nhon A1 - Valizadeh, Navid A1 - Nguyen, Manh Hung A1 - Nguyen-Xuan, Hung A1 - Zhuang, Xiaoying A1 - Areias, Pedro A1 - Zi, Goangseup A1 - Bazilevs, Yuri A1 - De Lorenzis, Laura A1 - Rabczuk, Timon T1 - An extended isogeometric thin shell analysis based on Kirchhoff-Love theory JF - Computer Methods in Applied Mechanics and Engineering N2 - An extended isogeometric thin shell analysis based on Kirchho_-Love theory KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 265 EP - 291 ER - TY - JOUR A1 - Anitescu, Cosmin A1 - Jia, Yue A1 - Zhang, Yongjie A1 - Rabczuk, Timon T1 - An isogeometric collocation method using superconvergent points JF - Computer Methods in Applied Mechanics and Engineer-ing N2 - An isogeometric collocation method using superconvergent points KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 1073 EP - 1097 ER - TY - JOUR A1 - Rabizadeh, Ehsan A1 - Saboor Bagherzadeh, Amir A1 - Rabczuk, Timon T1 - Application of goal-oriented error estimation and adaptive mesh refinement on thermo-mechanical multifield problems JF - Computational Materials Science N2 - Application of goal-oriented error estimation and adaptive mesh re_nement on thermo-mechanical multi_eld problems KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 27 EP - 44 ER - TY - JOUR A1 - Zhao, Jun-Hua A1 - Jia, Yue A1 - Wei, Ning A1 - Rabczuk, Timon T1 - Binding energy and mechanical stability of two parallel and crossing carbon nanotubes JF - Journal of Applied Mechanics N2 - Binding energy and mechanical stability of two parallel and crossing carbon nanotubes KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 ER - TY - JOUR A1 - Talebi, Hossein A1 - Silani, Mohammad A1 - Rabczuk, Timon T1 - Concurrent Multiscale Modelling of Three Dimensional Crack and Dislocation Propagation JF - Advances in Engineering Software N2 - Concurrent Multiscale Modelling of Three Dimensional Crack and Dislocation Propagation KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 82 EP - 92 ER - TY - JOUR A1 - Zhao, Jun-Hua A1 - Lu, Lixin A1 - Zhang, Zhiliang A1 - Guo, Wanlin A1 - Rabczuk, Timon T1 - Continuum modeling of the cohesive energy for the interfaces between _lms, spheres, coats and substrates JF - Computational Materials Science N2 - Continuum modeling of the cohesive energy for the interfaces between _lms, spheres, coats and substrates KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 432 EP - 438 ER - TY - JOUR A1 - Areias, Pedro A1 - Rabczuk, Timon A1 - Queiros de Melo, F. J. M. A1 - Cesar de Sa, J.M. T1 - Coulomb frictional contact by explicit projection in the cone for _nite displacement quasi-static problems JF - Computational Mechanics N2 - Coulomb frictional contact by explicit projection in the cone for _nite displacement quasi-static problems KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 57 EP - 72 ER - TY - JOUR A1 - Nanthakumar, S.S. A1 - Lahmer, Tom A1 - Zhuang, Xiaoying A1 - Zi, Goangseup A1 - Rabczuk, Timon T1 - Detection of material interfaces using a regularized level set method in piezoelectric structures JF - Inverse Problems in Science and Engineering N2 - Detection of material interfaces using a regularized level set method in piezoelectric structures KW - Angewandte Mathematik KW - Stochastik KW - Strukturmechanik Y1 - 2015 ER - TY - JOUR A1 - Budarapu, Pattabhi Ramaiah A1 - Narayana, T.S.S. A1 - Rammohan, B. A1 - Rabczuk, Timon T1 - Directionality of sound radiation from rectangular panels JF - Applied Acoustics N2 - Directionality of sound radiation from rectangular panels KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 128 EP - 140 ER - TY - JOUR A1 - Areias, Pedro A1 - Rabczuk, Timon A1 - Cesar de Sa, J.M. A1 - Garcao, J.E. T1 - Finite strain quadrilateral shell using least-squares _t of relative Lagrangian in-plane strains JF - Finite Elements in Analysis and Design N2 - Finite strain quadrilateral shell using least-squares _t of relative Lagrangian in-plane strains KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 26 EP - 40 ER - TY - JOUR A1 - Ghasemi, Hamid A1 - Kerfriden, Pierre A1 - Bordas, Stéphane Pierre Alain A1 - Muthu, Jacob A1 - Zi, Goangseup A1 - Rabczuk, Timon T1 - Interfacial shear stress optimization in sandwich beams with polymeric core using nonuniform distribution of reinforcing ingredients JF - Composite Structures N2 - Interfacial shear stress optimization in sandwich beams with polymeric core using nonuniform distribution of reinforcing ingredients KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 221 EP - 230 ER - TY - JOUR A1 - Thai, Chien H. A1 - Nguyen-Xuan, Hung A1 - Bordas, Stéphane Pierre Alain A1 - Nguyen-Thanh, Nhon A1 - Rabczuk, Timon T1 - Isogeometric analysis of laminated composite plates using the higher-order shear deformation theory JF - Mechanics of Advanced Materials and Structures N2 - Isogeometric analysis of laminated composite plates using the higher-order shear deformation theory KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 451 EP - 469 ER - TY - JOUR A1 - Mortazavi, Bohayra A1 - Cuniberti, G. A1 - Rabczuk, Timon T1 - Mechanical properties and thermal conductivity of graphitic carbon nitride: A molecular dynamics study JF - Computational Materials Science N2 - Mechanical properties and thermal conductivity of graphitic carbon nitride: A molecular dynamics study KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 285 EP - 289 ER - TY - JOUR A1 - Kumar, S. A1 - Singh, I. A1 - Mishra, B.K. A1 - Rabczuk, Timon T1 - Modeling and Simulation of Kinked Cracks by Virtual Node XFEM JF - Computer Methods in Applied Mechanics and Engineering N2 - Modeling and Simulation of Kinked Cracks by Virtual Node XFEM KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 1425 EP - 1466 ER - TY - JOUR A1 - Mortazavi, Bohayra A1 - Rabczuk, Timon T1 - Multiscale modeling of heat conduction in graphene laminates JF - Carbon N2 - Multiscale modeling of heat conduction in graphene laminates KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 1 EP - 7 ER - TY - JOUR A1 - Arash, Behrouz A1 - Rabczuk, Timon A1 - Jiang, Jin-Wu T1 - Nanoresonators and their applications: a state of the art review JF - Applied Physics Reviews N2 - Nanoresonators and their applications: a state of the art review KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 ER - TY - JOUR A1 - Ghasemi, Hamid A1 - Brighenti, Roberto A1 - Zhuang, Xiaoying A1 - Muthu, Jacob A1 - Rabczuk, Timon T1 - Optimum fiber content and distribution in fiber-reinforced solids using a reliability and NURBS based sequential optimization approach JF - Structural and Multidisciplinary Optimization N2 - Optimum _ber content and distribution in _ber-reinforced solids using a reliability and NURBS based sequential optimization approach KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 99 EP - 112 ER - TY - JOUR A1 - Hamdia, Khader A1 - Lahmer, Tom A1 - Nguyen-Thoi, T. A1 - Rabczuk, Timon T1 - Predicting The Fracture Toughness of PNCs: A Stochastic Approach Based on ANN and ANFIS JF - Computational Materials Science N2 - Predicting The Fracture Toughness of PNCs: A Stochastic Approach Based on ANN and ANFIS KW - Angewandte Mathematik KW - Stochastik KW - Strukturmechanik Y1 - 2015 SP - 304 EP - 313 ER - TY - JOUR A1 - Ghorashi, Seyed Shahram A1 - Valizadeh, Navid A1 - Mohammadi, S. A1 - Rabczuk, Timon T1 - T-spline based XIGA for Fracture Analysis of Orthotropic Media JF - Computers & Structures N2 - T-spline based XIGA for Fracture Analysis of Orthotropic Media KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 138 EP - 146 ER - TY - JOUR A1 - Ben, S. A1 - Zhao, Jun-Hua A1 - Zhang, Yancheng A1 - Rabczuk, Timon T1 - The interface strength and debonding for composite structures: review and recent developments JF - Composite Structures N2 - The interface strength and debonding for composite structures: review and recent developments KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 ER - TY - JOUR A1 - Zhao, Jiyun A1 - Lu, Lixin A1 - Rabczuk, Timon T1 - The tensile and shear failure behavior dependence on chain length and temperature in amorphous polymers JF - Computational Materials Science N2 - The tensile and shear failure behavior dependence on chain length and temperature in amorphous polymers KW - Angewandte Mathematik KW - Strukturmechanik Y1 - 2015 SP - 567 EP - 572 ER - TY - JOUR A1 - Vu-Bac, N. A1 - Rafiee, Roham A1 - Zhuang, Xiaoying A1 - Lahmer, Tom A1 - Rabczuk, Timon T1 - Uncertainty quantification for multiscale modeling of polymer nanocomposites with correlated parameters JF - Composites Part B: Engineering N2 - Uncertainty quantification for multiscale modeling of polymer nanocomposites with correlated parameters KW - Angewandte Mathematik KW - Stochastik KW - Strukturmechanik Y1 - 2015 SP - 446 EP - 464 ER - TY - JOUR A1 - Lahmer, Tom A1 - Ilg, J. A1 - Lerch, Reinhard T1 - Variance-based sensitivity analyses of piezoelectric models JF - Computer Modeling in Engineering & Sciences N2 - Variance-based sensitivity analyses of piezoelectric models KW - Angewandte Mathematik KW - Stochastik KW - Strukturmechanik Y1 - 2015 SP - 105 EP - 126 ER -