varunr14/newsummary huggingface dataset:
In this paper 4 node quadrilateral and 3 node triangular solid shell elements are applied to drape simulations . With locking issues alleviated by the assumed natural strain method and plane stress enforcement static and dynamic drape problems are attempted by the quadrilateral element . If the drape is deep and the mesh density is inadequate non realistic sharp folds are predicted due to the non physical interpenetration of top and bottom element surfaces . To avoid the interpenetration a reversible adaptive subdivision based on the 1 4 splitting method is developed . To ensure displacement compatibility among elements at different subdivision levels macro transition elements are formed by quadrilateral and triangular solid shell elements . To reduce the dynamic oscillation induced by newly inserted nodes the discrete Kirchhoff condition is employed to determine the related nodal variables . Dynamic drape examples using adaptive meshing are presented . It can be seen that the predictions look realistic and deep drapes can be predicted with the interpenetration avoided yet the required number of nodes can be kept relatively small . 


Highlights:
Solid shell elements attending shear trapezoidal and thickness locking are employed. To avoid interpenetration a curvature based reversible adaptive meshing is devised. Kirchhoff condition is employed to reduce dynamic oscillation of new inserted nodes. The predicted drape shapes appear to be realistic with interpenetration avoided.
This paper proposes a strategy for the efficient implementation of Fixed Grid Finite Element Analysis method on Graphics Processing Units . Such a strategy makes use of grid regularity of FGFEA to reduce drastically both the memory required by the implementation and the memory transactions to perform the operations with the common elemental stiffness matrix . The matrix free method is adopted to reduce the memory requirements obviating the assembly process of FEA and to exploit the parallelization potential of GPU architectures performing matrix vector products at the Degree of Freedom level . The underlying idea is to exploit data locality and maximize the use of on chip memory which increase notably the performance of GPU computing . The numerical experiments show that the proposed matrix free GPU instance of FGFEA can achieve significant speedup over classical sparse matrix CPU implementation using similar iterative solver . 


Highlights:
Efficient strategy for GPU computing of FGFEA is proposed. Data locality is exploited to achieve notable GPU performance. Required device memory is minimized replacing it by efficient parallel calculations. Significant speedup with respect to sparse matrix CPU implementation is achieved.
A new adaptive multiscale method is developed based on the estimate of residual forces for static analysis of heterogeneous materials . The AMM is established by combining multi node extended multiscale finite element method with a new proposed macroscopic node adaptive algorithm . In our previous multiscale computations macroscopic nodes are placed uniformly along each edge of multi node coarse element without considering local strain or displacement gradient . In this paper to optimize the distribution of macroscopic nodes a new adaptive algorithm is proposed based on the estimate of residual forces . Numerical experiments have indicated that residual forces exist even for linear elastic problems . For boundary external loading cases residual forces only exist on the edges of coarse element . Besides computations indicate that residual forces can reflect local relative errors in the multi node EMsFEM computations . Thus it is reasonable and suitable to take residual forces as local relative error indicators in the multi node EMsFEM computations . Finally the AMM is developed based on this idea . To verify the validity of this proposed method three typical numerical examples are carried out . The examples demonstrate that nearly optimal distributions of macroscopic nodes can be obtained by employing the proposed AMM . 


Highlights:
A new adaptive multiscale method AMM is developed. The estimate of residual force is taken as local relative error indicator. The validity of the proposed algorithm has been verified. Nearly optimal distribution of macroscopic nodes can be found by using AMM.
A nonlocal extension of the damage plasticity model CDPM2 is proposed . The performance of this extension is evaluated in comparison with a crack band version of the same model for describing the failure of reinforced concrete . In particular the influence of mesh size on the structural response in the form of load displacement curves and strain distributions is studied for a reinforced concrete beam subjected to four point bending . The nonlocal model provides mesh independent load displacement curves and strain profiles whereas the peak loads and strain profiles obtained with the crack band model depend on the element size . 


Highlights:
A new nonlocal damage plasticity model has been proposed. The model has been applied to analyse plain and reinforced concrete members. The results of the nonlocal model are compared to those of a crack band approach. The influence of mesh size for the two modelling approaches has been investigated. The nonlocal model yields mesh independent results.
This paper describes the development of a reduced model of a fastener using Multi Connected Rigid Surfaces . The stiffness of the connectors is determined based on a physical approach considering different deformation modes of the bolt . The reduced model is constructed and identified from a numerical simulation of a single lap reference joint under tensile load with the adherent parts and bolts represented by 3 D solid elements . A single simulation with a given clearance axial preload and friction coefficient is used to identify equivalent stiffnesses . The reduced model is then compared with the 3 D solid elements model in a two fastener configuration for different values of clearance preload and friction coefficient . The comparison covers overall response in terms of stiffness and load distribution between fasteners local response in terms of stress fields and calculation times . Results show that the reduced model proposed here is able to reduce calculation times while still providing a good estimate of the mechanical quantities needed for the study and dimensioning of multi fastener joints . 


Highlights:
A finite element model of bolt is proposed to reduce time calculation of fastened joints. Different deformation modes of bolt are analysed to justify model construction. The bolt is represented by rigid surfaces linked with elastic connectors. The proposed model provide high precision load distribution and local stress field.