@article{ChenNguyenThanhNguyenXuanetal., author = {Chen, Lei and Nguyen-Thanh, Nhon and Nguyen-Xuan, Hung and Rabczuk, Timon and Bordas, St{\´e}phane Pierre Alain and Limbert, Georges}, title = {Explicit finite deformation analysis of isogeometric membranes}, series = {Computer Methods in Applied Mechanics and Engineering}, journal = {Computer Methods in Applied Mechanics and Engineering}, pages = {104 -- 130}, abstract = {Explicit finite deformation analysis of isogeometric membranes}, subject = {Angewandte Mathematik}, language = {en} } @phdthesis{NguyenThanh, author = {Nguyen-Thanh, Nhon}, title = {Isogeometric analysis based on rational splines over hierarchical T-mesh and alpha finite element method for structural analysis}, issn = {1610-7381}, doi = {10.25643/bauhaus-universitaet.2078}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20131125-20781}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {196}, abstract = {This thesis presents two new methods in finite elements and isogeometric analysis for structural analysis. The first method proposes an alternative alpha finite element method using triangular elements. In this method, the piecewise constant strain field of linear triangular finite element method models is enhanced by additional strain terms with an adjustable parameter a, which results in an effectively softer stiffness formulation compared to a linear triangular element. In order to avoid the transverse shear locking of Reissner-Mindlin plates analysis the alpha finite element method is coupled with a discrete shear gap technique for triangular elements to significantly improve the accuracy of the standard triangular finite elements. The basic idea behind this element formulation is to approximate displacements and rotations as in the standard finite element method, but to construct the bending, geometrical and shear strains using node-based smoothing domains. Several numerical examples are presented and show that the alpha FEM gives a good agreement compared to several other methods in the literature. Second method, isogeometric analysis based on rational splines over hierarchical T-meshes (RHT-splines) is proposed. The RHT-splines are a generalization of Non-Uniform Rational B-splines (NURBS) over hierarchical T-meshes, which is a piecewise bicubic polynomial over a hierarchical T-mesh. The RHT-splines basis functions not only inherit all the properties of NURBS such as non-negativity, local support and partition of unity but also more importantly as the capability of joining geometric objects without gaps, preserving higher order continuity everywhere and allow local refinement and adaptivity. In order to drive the adaptive refinement, an efficient recovery-based error estimator is employed. For this problem an imaginary surface is defined. The imaginary surface is basically constructed by RHT-splines basis functions which is used for approximation and interpolation functions as well as the construction of the recovered stress components. Numerical investigations prove that the proposed method is capable to obtain results with higher accuracy and convergence rate than NURBS results.}, subject = {Isogeometric analysis}, language = {en} } @article{NguyenThanhKiendlNguyenXuanetal., author = {Nguyen-Thanh, Nhon and Kiendl, J. and Nguyen-Xuan, Hung and W{\"u}chner, R. and Bletzinger, Kai-Uwe and Bazilevs, Yuri and Rabczuk, Timon}, title = {Rotation free isogeometric thin shell analysis using PHT-splines}, series = {Computer Methods in Applied Mechanics and Engineering}, journal = {Computer Methods in Applied Mechanics and Engineering}, pages = {3410 -- 3424}, abstract = {Rotation free isogeometric thin shell analysis using PHT-splines}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenThanhMuthuZhuangetal., author = {Nguyen-Thanh, Nhon and Muthu, Jacob and Zhuang, Xiaoying and Rabczuk, Timon}, title = {An adaptive three-dimensional RHT-splines formulation in linear elasto-statics and elasto-dynamics}, series = {Computational Mechanics}, journal = {Computational Mechanics}, pages = {369 -- 385}, abstract = {An adaptive three-dimensional RHT-splines formulation in linear elasto-statics and elasto-dynamics}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenThanhNguyenXuanBordasetal., author = {Nguyen-Thanh, Nhon and Nguyen-Xuan, Hung and Bordas, St{\´e}phane Pierre Alain and Rabczuk, Timon}, title = {Isogeometric analysis using polynomial splines over hierarchical T-meshes for two-dimensional elastic solids}, series = {Computer Methods in Applied Mechanics and Engineering}, journal = {Computer Methods in Applied Mechanics and Engineering}, pages = {1892 -- 1908}, abstract = {Isogeometric analysis using polynomial splines over hierarchical T-meshes for two-dimensional elastic solids}, subject = {Angewandte Mathematik}, language = {en} } @inproceedings{NguyenThanhRabczuk, author = {Nguyen-Thanh, Nhon and Rabczuk, Timon}, title = {A SMOOTHED FINITE ELEMENT METHOD FOR THE STATIC AND FREE VIBRATION ANALYSIS OF SHELLS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2877}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28777}, pages = {24}, abstract = {A four-node quadrilateral shell element with smoothed membrane-bending based on Mindlin-Reissner theory is proposed. The element is a combination of a plate bending and membrane element. It is based on mixed interpolation where the bending and membrane stiffness matrices are calculated on the boundaries of the smoothing cells while the shear terms are approximated by independent interpolation functions in natural coordinates. The proposed element is robust, computationally inexpensive and free of locking. Since the integration is done on the element boundaries for the bending and membrane terms, the element is more accurate than the MITC4 element for distorted meshes. This will be demonstrated for several numerical examples.}, subject = {Angewandte Informatik}, language = {en} } @article{NguyenThanhRabczukNguyenXuanetal., author = {Nguyen-Thanh, Nhon and Rabczuk, Timon and Nguyen-Xuan, Hung and Bordas, St{\´e}phane Pierre Alain}, title = {An alternative alpha finite element method with stabilized discrete shear gap technique for analysis of Mindlin-Reissner plates}, series = {Finite Elements in Analysis \& Design}, journal = {Finite Elements in Analysis \& Design}, pages = {519 -- 535}, abstract = {An alternative alpha finite element method with stabilized discrete shear gap technique for analysis of Mindlin-Reissner plates}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenThanhRabczukNguyenXuanetal., author = {Nguyen-Thanh, Nhon and Rabczuk, Timon and Nguyen-Xuan, Hung and Bordas, St{\´e}phane Pierre Alain}, title = {An alternative alpha finite element method (A?FEM) free and forced vibration analysis of solids using triangular meshes}, series = {Journal of Computational and Applied Mathematics}, journal = {Journal of Computational and Applied Mathematics}, pages = {2112 -- 2135}, abstract = {An alternative alpha finite element method (A?FEM) free and forced vibration analysis of solids using triangular meshes}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenThanhThaiHoangNguyenXuanetal., author = {Nguyen-Thanh, Nhon and Thai-Hoang, C. and Nguyen-Xuan, Hung and Rabczuk, Timon}, title = {A smoothed finite element method for the static and free vibration analysis of shells}, series = {Journal of Civil Engineering and Architecture}, journal = {Journal of Civil Engineering and Architecture}, pages = {13 -- 25}, abstract = {A smoothed finite element method for the static and free vibration analysis of shells}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenThanhValizadehNguyenetal., author = {Nguyen-Thanh, Nhon and Valizadeh, Navid and Nguyen, Manh Hung and Nguyen-Xuan, Hung and Zhuang, Xiaoying and Areias, Pedro and Zi, Goangseup and Bazilevs, Yuri and De Lorenzis, Laura and Rabczuk, Timon}, title = {An extended isogeometric thin shell analysis based on Kirchhoff-Love theory}, series = {Computer Methods in Applied Mechanics and Engineering}, journal = {Computer Methods in Applied Mechanics and Engineering}, pages = {265 -- 291}, abstract = {An extended isogeometric thin shell analysis based on Kirchho_-Love theory}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenXuanRabczukNguyenThanhetal., author = {Nguyen-Xuan, Hung and Rabczuk, Timon and Nguyen-Thanh, Nhon and Nguyen-Thoi, T. and Bordas, St{\´e}phane Pierre Alain}, title = {A node-based smoothed finite element method (NS-FEM) for analysis of Reissner-Mindlin plates}, series = {Computational Mechanics}, journal = {Computational Mechanics}, pages = {679 -- 701}, abstract = {A node-based smoothed finite element method (NS-FEM) for analysis of Reissner-Mindlin plates}, subject = {Angewandte Mathematik}, language = {en} } @article{NguyenXuanRabczukNguyenThoietal., author = {Nguyen-Xuan, Hung and Rabczuk, Timon and Nguyen-Thoi, T. and Tran, T. and Nguyen-Thanh, Nhon}, title = {Computation of limit and shakedown loads using a node-based smoothed finite element method}, series = {International Journal for Numerical Methods in Engineering}, journal = {International Journal for Numerical Methods in Engineering}, doi = {10.1002/nme.3317}, pages = {287 -- 310}, abstract = {This paper presents a novel numerical procedure for computing limit and shakedown loads of structures using a node-based smoothed FEM in combination with a primal-dual algorithm. An associated primal-dual form based on the von Mises yield criterion is adopted. The primal-dual algorithm together with a Newton-like iteration are then used to solve this associated primal-dual form to determine simultaneously both approximate upper and quasi-lower bounds of the plastic collapse limit and the shakedown limit. The present formulation uses only linear approximations and its implementation into finite element programs is quite simple. Several numerical examples are given to show the reliability, accuracy, and generality of the present formulation compared with other available methods.}, subject = {Angewandte Mathematik}, language = {en} } @article{ThaiNguyenXuanBordasetal., author = {Thai, Chien H. and Nguyen-Xuan, Hung and Bordas, St{\´e}phane Pierre Alain and Nguyen-Thanh, Nhon and Rabczuk, Timon}, title = {Isogeometric analysis of laminated composite plates using the higher-order shear deformation theory}, series = {Mechanics of Advanced Materials and Structures}, journal = {Mechanics of Advanced Materials and Structures}, pages = {451 -- 469}, abstract = {Isogeometric analysis of laminated composite plates using the higher-order shear deformation theory}, subject = {Angewandte Mathematik}, language = {en} } @article{ThaiNguyenXuanNguyenThanhetal., author = {Thai, Chien H. and Nguyen-Xuan, Hung and Nguyen-Thanh, Nhon and Le, T.H. and Nguyen-Thoi, T. and Rabczuk, Timon}, title = {Static, free vibration and buckling analysis of laminated composite Reissner-Mindlin plates using NURBS-based isogeometric approach}, series = {International Journal for Numerical Methods in Engineering}, journal = {International Journal for Numerical Methods in Engineering}, doi = {10.1002/nme.4282}, pages = {571 -- 603}, abstract = {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.}, subject = {Angewandte Mathematik}, language = {en} }