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Showing 1 to 20 of 20 for “"Updated Lagrangian"”.
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A mixed computational algorithm based on the updated Lagrangian description for plane elastic contact problems
… small strains) under external loads using the updated Lagrangian formulation. The mixed finite element formulation allows the nodal displacements and stresses to be approximated independently. Inclusion of stresses as the nodal variables allows the satisfaction of stress equilibrium and contact …
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Nonlinear finite element analysis of sheet pile interlocks
… effect due to multi-contact surfaces. The Updated Lagrangian formulation is adopted in this study. When the response is in elastic range the Updated Lagrangian with Transformation is used while the Updated Lagrangian with Jaumann stress rate is employed when the element starts to yield. An …
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Nonlinear analysis of cable structures
… element method are derived in both the Total Lagrangian and Updated Lagrangian form. The Updated Lagrangian equations are then specialized for the analysis of three-dimensional cable structures. Two node and three node isoparametric finite elements are derived and a program is developed which …
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Geometrically nonlinear finite element analysis of space frames
… of the finite element is adopted. Both the updated Lagrangian formulation and total Lagrangian formulation of a three-dimensional beam element is employed for large displacement and large rotation, but small strain analysis. A beam-column element or finite element can be used to model …
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Comparison of nonlinear finite element formulations: application to trusses
… in addition to an overview of the Total and Updated Lagrangian reference frames, serve as the starting point for this review. The two nonlinear formulations are specialized for use with a geometrically nonlinear plane truss finite element. The truss formulations are then implemented into …
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Numerical modeling of strain localization in granular materials using Cosserat theory enhanced with microfabric properties
Finite element solution in the updated Lagrangian frame is used to investigate the strain localization phenomenon "shear bands" in granular materials. The micro-polar theory was used as the mathematical foundation for the continuum formulations. A laboratory testing results are used for …
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A finite element analysis of adhesively bonded composite joints including geometric nonlinearity, nonlinear viscoelasticity, moisture diffusion and delayed failure
… adhesive are taken into account by invoking the updated Lagrangian description of motion. The adhesive layer is modeled using Schapery's nonlinear single integral constitutive law for uniaxial and multiaxial states of stress. Effect of temperature and stress level on the viscoelastic response is …
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Development and Applications of a Flat Triangular Element for Thin Laminated Shells
… nonlinear analysis is performed using an updated Lagrangian formulation employing Green strain and Second Piola-Kirchhoff (PK2) stress measures. A linear displacement field is used for the transverse displacement in order to compute the derivatives of the transverse displacement that are …
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Finite element analysis of elastic-plastic anisotropic soils
… in which the models are implemented. An updated Lagrangian large displacement analysis is also included. The constitutive models developed are used to investigate the influence of initial anisotropy on the bearing capacity, deformation and pore pressure development under footings in both …
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Resposta dinâmica e estabilidade de tubos com escoamento interno
… of pipes conveying fluid. Making use of an updated lagrangian formulation for the principle of virtual work the incremental equations of motion are deduced. These equations are linearized about the equilibrium configuration and the free vibration problem is discussed, showing that an …
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Stress analysis of rocket motors with viscoelastic propellant by a mixed finite element model
… body under external symmetric loads using the updated Lagrangian formulation. The mixed finite element formulation treats the nodal displacements and stresses as the variables that can be approximated independently. The method of static condensation is used to keep some stresses across …
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Development and implementation of a combined discrete and finite element multibody dynamics simulation environment
… simulation. In order to achieve this goal, an Updated Lagrangian (UL) Finite Element (FE) formulation and an explicit time integration scheme have been employed together with some simplifiying assumptions to linearize this highly nonlinear contact problem and obtain solutions with realistic …
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A Tool Wear Comparative Study in Turning Versus Computer Simulation in 1018 Steel
… the world for research. This thesis used an updated Lagrangian model in conjunction with Archard's law to predict the wear of the cutting tool. This research used experimental data to correlate with simulation data to see whether or not Archard's law was a good approximation for tool wear. …
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Nonlinear mixed finite element analysis for contact problems by a penalty constraint technique
… stress analysis. The formulation is based on the updated Lagrangian approach and accounts for geometric nonlinearity. In the mixed model, both displacements and stresses are approximated independently and this approach has in general been found to be more accurate than the displacement finite …
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Friction models in the solution of nonstationary contact problems
… contact problem is then formulated in the Total Lagrangian and Updated Lagrangian formulations for contact between an elastic-plastic (Mises plasticity) body and a rigid tool. The variational (weak) form of the formulation is given and this is then discretised by the finite element method. To …
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Large deformation analysis of laminated composite structures by a continuum-based shell element with transverse deformation
… laminated shell theory is formulated using the Updated Lagrangian description of a general continuum-based theory with assumptions on thickness deformation. The transverse deflection is approximated through the thickness by a quartic polynomial of the thickness coordinate. As a result both the …
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Aeroelastic Analysis of Rotor Blades Using Three Dimensional Flexible Multibody Dynamic Analysis
… frame by using the co-rotational form of the updated Lagrangian description of motion. The implicit integration scheme is based on the Generalized-alpha method, and kinematic joints are invoked in the formulation through the coordinate partitioning method. The resulting numerical scheme …
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A study of building response and damage due to mining-induced ground movements
… beam, transition and friction elements. Total Lagrangian (T.L.) formulation is used for plane elements and Updated Lagrangian (U.L.) formulation for beam, transition, and friction elements. The program consists of twenty six subroutines and requires about one mega-bytes of memory. It can model …
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A small strain, large rotation theory and finite element formulation of thin curved beams
… system, has been developed. Four alternative Lagrangian formulations of the theory have been presented for comparison. A family of two-dimensional thin curved beam elements has been developed by using the constraint technique to include the convective coordinate system. The elements are …
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Numerical modelling of time-dependent cracking and deformation of reinforced concrete structures
… deformation was also accounted for using the updated Lagrangian formulation. The numerical models were used to simulate a series of laboratory tests for verification purposes. The models were assessed critically by comparing the numerical results with the test data and the numerical results …