A Global Bolted Joint Model for Finite Element Simulations of Large-scale Composite Structures

2009 ◽  
Author(s):  
P.J. Gray ◽  
C.T. McCarthy
Keyword(s):  
Finite Element ◽  
Composite Structures ◽  
Large Scale ◽  
Joint Model ◽  
Finite Element Simulations ◽  
Bolted Joint

Influence of the Bolt Material Properties on the Ultimate Capacity of End Plate Bolted Joint Subjected to Column Loss

2021 ◽  
Vol 885 ◽  
pp. 133-139
Author(s):  
Roberto Tartaglia ◽  
Alessia Campiche
Keyword(s):  
Finite Element ◽  
Numerical Model ◽  
Material Properties ◽  
Finite Element Simulations ◽  
Material Strength ◽  
Bolted Joint ◽  
Ultimate Capacity ◽  
Catenary Action ◽  
Beneficial Effects ◽  
End Plate

This paper investigates the performance of extended stiffened end-plate bolted beam-to-column joints subjected a column loss scenario by means of finite element simulations. An advanced numerical model was developed, and its effectiveness was validated against the experimental results. The influence of the bolt strengthening on the column loss action was investigated changing the grade of bolts. The results showed that the joint performance under column loss scenario are deeply related to the development of the catenary action that depends from the connection ductility; therefore increasing the bolt material strength will provide beneficial effects on the joint capacity under the column loss.

Clamp Load Loss in a Bolted Joint Model With Plastic Bolt Elongation and Eccentric Service Load

2010 ◽  
Author(s):  
Xianjie Yang ◽  
Sayed Nassar ◽  
Zhijun Wu ◽  
Aidong Meng
Keyword(s):  
Plastic Deformation ◽  
Finite Element ◽  
Experimental Verification ◽  
Deformation Behavior ◽  
Joint Model ◽  
Bolted Joint ◽  
Linear Elastic ◽  
Plastic Deformation Behavior ◽  
Service Load ◽  
Joint Material

The nonlinear plastic deformation behavior of a clamped bolted joint model under a separating service load is investigated using analytical, finite element, and experimental techniques. An elastic-plastic model is used for the bolt material while the joint material remains in the linear elastic range. Both the analytical and FEA models investigate the variation in the tension of a preloaded bolt, and the corresponding change in the joint clamp load, due to a separating service load that is placed away from the bolt center. Experimental verification is provided for both the analytical and finite element results on the bolt tension variation, clamp load variation and the clamp load loss caused by the incremental plastic bolt elongation under cyclic separating force.

Automated Parallel and Body-Fitted Mesh Generation in Finite Element Simulation of Macromolecular Systems

2016 ◽  
Vol 19 (3) ◽  
pp. 582-602 ◽  
Author(s):  
Yan Xie ◽  
Tiantian Liu ◽  
Bin Tu ◽  
Benzhuo Lu ◽  
Linbo Zhang
Keyword(s):  
Finite Element ◽  
Mesh Generation ◽  
Large Scale ◽  
Molecular Shape ◽  
Finite Element Simulations ◽  
Molecular Surface ◽  
Immersed Boundary ◽  
Adaptive Finite Element ◽  
Space Filling Curve ◽  
Mesh Refinements

AbstractMesh generation is a bottleneck for finite element simulations of biomolecules. A robust and efficient approach, based on the immersed boundary method proposed in [8], has been developed and implemented to generate large-scale mesh body-fitted to molecular shape for general parallel finite element simulations. The molecular Gaussian surface is adopted to represent the molecular surface, and is finally approximated by piecewise planes via the tool phgSurfaceCut in PHG [43], which is improved and can reliably handle complicated molecular surfaces, through mesh refinement steps. A coarse background mesh is imported first and then is distributed into each process using a mesh partitioning algorithm such as space filling curve [5] or METIS [22]. A bisection method is used for the mesh refinements according to the molecular PDB or PQR file which describes the biomolecular region. After mesh refinements, the mesh is optionally repartitioned and redistributed for load balancing. For finite element simulations, the modification of region mark and boundary types is done in parallel. Our parallel mesh generation method has been successfully applied to a sphere cavity model, a DNA fragment, a gramicidin A channel and a huge Dengue virus system. The results of numerical experiments show good parallel efficiency. Computations of electrostatic potential and solvation energy also validate the method. Moreover, the meshing process and adaptive finite element computation can be integrated as one PHG project to avoid the mesh importing and exporting costs, and improve the convenience of application as well.

scholarly journals Engineering optimization of decompressive craniectomy based on finite element simulations

2020 ◽  
Vol 22 (4) ◽  
Author(s):  
Máté Hazay ◽  
Emese Nagy ◽  
Péter Tóth ◽  
András Büki ◽  
Imre Bojtár
Keyword(s):  
Finite Element ◽  
Decompressive Craniectomy ◽  
Input Data ◽  
Large Scale ◽  
Parametric Optimization ◽  
Finite Element Simulations ◽  
Nonlinear Dependence ◽  
Patient Specific ◽  
Optimal Size ◽  
Optimization Study

Purpose: The optimal execution of decompressive craniectomy in terms of the size and location of the skull opening is not straightforward. Our main goals are twofold: (1) constructing a design optimization method which can be applied to determine optimal skull opening for individual patient-specific cases and (2) performing a large-scale parametric optimization study to give some guidance in general about the optimal skull opening in case of oedematous brain tissue. Methods: A large number of virtual experiments performed by finite element simulations were applied to determine tendencies of tissue behaviour during surgery. The multiobjective optimization is performed by Goal Programming and Physical Programming methods. Results: Our results show that the postoperative pressure has an approximately linear dependence on the preoperative pressure and the skull opening area, while the damaged brain volume could have a more complex nonlinear dependence on the input data. Based on the averaged results of the parametric optimization study, the optimal skull opening has been determined in the function of the preoperative pressure and the relative importance of the pressure reduction. These results show that the optimal size of the unilateral skull opening is usually between 130–180 cm2 and these openings are more beneficial than the currently analysed bifrontal openings. Conclusions: The optimal skull opening is patient-specific and depends on several input data. The presented methodology can be applied to optimize surgery based on these input parameters for different injury types. Based on the results of large-scale parametric study generally applicable approximate results have been provided.

Sign in / Sign up

Export Citation Format

Share Document