Modeling the Crushing Response of PMC Tubes Under Quasi-Static and Dynamic Loading Conditions

2002 ◽  
Author(s):  
M. Abdel-Haq ◽  
G. Newaz
Keyword(s):  
Finite Element ◽  
Energy Absorption ◽  
Failure Modes ◽  
Peak Load ◽  
Finite Element Models ◽  
Failure Model ◽  
Axial Splitting ◽  
Element Technique ◽  
Dynamic Loading Conditions ◽  
Static And Dynamic Loading

Non-linear finite element technique was used to predict the crushing response and energy absorption of fiberglass/polyester tubes under quasi-static and dynamic conditions. The major failure modes including axial splitting of the tube wall and delamination were modeled using the available features in LSDYNA and ABAQUS codes for dynamic and quasi-static analysis, respectively. The results show that the finite element models were able to predict the average and peak load levels for the tubes with and without using an external constraint. Finally, it was concluded that modeling the major failure modes in the crushing process in addition to using an appropriate material failure model is essential to capture the load levels and specific energy absorption of the crushed tubes.

Experimental and numerical studies on failure and energy absorption of composite thin-walled square tubes under quasi-static compression loading

2020 ◽  
Vol 21 (6) ◽  
pp. 623-634
Author(s):  
Haolei Mou ◽  
Zhenyu Feng ◽  
Jiang Xie ◽  
Jun Zou ◽  
Kun Zhou
Keyword(s):  
Finite Element ◽  
Shell Model ◽  
Energy Absorption ◽  
Failure Mode ◽  
Failure Criterion ◽  
Finite Element Models ◽  
Static Compression ◽  
Compression Loading ◽  
Thin Walled ◽  
Simulation Results

AbstractTo analysis the failure and energy absorption of carbon fiber reinforced polymer (CFRP) thin-walled square tube, the quasi-static axial compression loading tests are conducted for [±45]3s square tube, and the square tube after test is scanned to further investigate the failure mechanism. Three different finite element models, i.e. single-layer shell model, multi-layer shell model and stacked shell mode, are developed by using the Puck 2000 matrix failure criterion and Yamada Sun fiber failure criterion, and three models are verified and compared according to the experimental energy absorption metrics. The experimental and simulation results show that the failure mode of [±45]3s square tube is the local buckling failure mode, and the energy are absorbed mainly by intralaminar and interlaminar delamination, fiber elastic deformation, fiber debonding and fracture, matrix deformation cracking and longitudinal crack propagation. Three different finite element models can reproduce the collapse behaviours of [±45]3s square tube to some extent, but the stacked shell model can better reproduce the failure mode, and the difference of specific energy absorption (SEA) is minimum, which shows the numerical simulation results are in better agreement with the test results.

Experimental and Numerical Plastic Response and Failure of Laterally Impacted Rectangular Plates

2013 ◽  
Vol 135 (4) ◽  
Author(s):  
B. Liu ◽  
R. Villavicencio ◽  
C. Guedes Soares
Keyword(s):  
Finite Element ◽  
Numerical Simulations ◽  
Failure Modes ◽  
Mesh Size ◽  
Plastic Behavior ◽  
Finite Element Models ◽  
Rectangular Plates ◽  
Marine Structures ◽  
Fine Mesh ◽  
The Impact

Experimental and numerical results of drop weight impact test are presented on the plastic behavior and fracture of rectangular plates stuck laterally by a mass with a hemispherical indenter. Six specimens were tested in order to study the influence of the impact velocity and the diameter of the indenter. The impact scenarios could represent abnormal actions on marine structures, such as ship collision and grounding or dropped objects on deck structures. The tests are conducted on a fully instrumented impact tester machine. The obtained force-displacement response is compared with numerical simulations, performed by the LS-DYNA finite element solver. The simulations aim at proposing techniques for defining the material and restraints on finite element models which analyze the crashworthiness of marine structures. The mesh size and the critical failure strain are predicted by numerical simulations of the tensile tests used to obtain the mechanical properties of the material. The experimental boundary conditions are modeled in order to represent the reacting forces developed during the impact. The results show that the critical impact energy until failure is strongly sensitive to the diameter of the striker. The shape of the failure modes is well predicted by the finite element models when a relatively fine mesh is used. Comments on the process of initiation and propagation of fracture are presented.

Failure Prediction of Flip Chip Packages Using Finite Element Technique

2002 ◽  
Author(s):  
Abm Hasan ◽  
H. Mahfuz ◽  
M. Saha ◽  
S. Jeelani
Keyword(s):  
Finite Element ◽  
Flip Chip ◽  
Thermal Loading ◽  
Failure Modes ◽  
Element Model ◽  
Thermally Induced ◽  
Operational Life ◽  
Flip Chip Assembly ◽  
The Individual ◽  
Element Technique

Flip-chip electronic package undergoes thermal loading during its curing process and operational life. Due to the thermal expansion coefficient (CTE) mismatch of various components, the flip-chip assembly experiences various types of thermally induced stresses and strains. Experimental measurement of these stresses and strains is extremely tedious and rigorous due to the physical limitations in the dimensions of the flip-chip assembly. While experiments provide accurate assessment of stresses and strains at certain locations, a parallel finite element (FE) analysis and analytical study can complementarily determine the displacement, strain and stress fields over the entire region of the flip-chip assembly. Such combination of experimental, finite element and analytical studies are ideal to yield a successful stress analysis of the flip-chip assembly under the various loading conditions. In this study, a two-dimensional finite element model of the flip-chip consisting of the silicon chip, underfill, solder ball, copper pad, solder mask and substrate has been developed. Various stress components under thermal loading condition ranging from −40°C to 150°C have been determined using both the finite element and analytical methods. Stresses such as (σ11, σ12, ε12 etc. are extracted and analyzed for the individual components as well as the entire assembly, and the weakest positions of the flip-chip have been discovered. Detailed description of FE modeling is presented and the different failure modes of chip assembly are discussed.

Behaviour of hollow concrete masonry walls with one-course bond beams subjected to concentric and eccentric concentrated loading

2003 ◽  
Vol 30 (1) ◽  
pp. 181-190 ◽  
Author(s):  
Junyi Yi ◽  
Nigel G Shrive
Keyword(s):  
Finite Element ◽  
Failure Modes ◽  
Three Dimensional ◽  
Masonry Walls ◽  
Finite Element Models ◽  
Concentrated Load ◽  
Concrete Masonry ◽  
Out Of Plane ◽  
Concentrated Loading ◽  
Concrete Masonry Walls

Three-dimensional finite element models of unreinforced hollow concrete masonry walls with one-course bond beams subjected to concentrated loading have been analyzed. The walls were modelled with different loading plate sizes, different loading locations along the wall (at the midpoint of the wall, at the end of the wall, and between these points), and different out-of-plane eccentricities (e = 0, t/6, and t/3). The hollow block units, mortar, grout, and bond beam blocks in the walls were modelled separately. Both smeared and discrete cracking methods have been utilized for predicting cracking under load. Geometric and material nonlinearities and damage due to progressive cracking were taken into account in the analyses. The predicted failure modes and ultimate capacities of the walls with the concentric concentrated load applied at the midpoint or at the end of the wall compared very well with the experimental results. When the load was between the midpoint and the end of the wall, the predicted ultimate capacity was between those for the load at the midpoint and at the end. The strength of the walls decreases with increasing out-of-plane eccentricities.Key words: finite element models, hollow masonry, smeared and discrete cracking models, concentrated load, loading locations, out-of-plane eccentricities.

scholarly journals Numerical modelling strategies using implicit and explicit methods to simulate quasi-static and dynamic three-points bend fracture tests of a ductile steel

2021 ◽  
Vol 250 ◽  
pp. 02033
Author(s):  
Frédéric Nozères ◽  
Hervé Couque ◽  
Rémi Boulanger ◽  
Yann Quirion ◽  
Patrice Bailly ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Crack Initiation ◽  
Crack Initiation And Propagation ◽  
Initiation And Propagation ◽  
Fracture Tests ◽  
Point Bend ◽  
Dynamic Loading Conditions ◽  
Implicit And Explicit ◽  
Static And Dynamic Loading

Three-point bend fracture tests have been conducted at different loading rates with a quadratic martensitic steel. The failure energy has been found to increase with loading rate. To get insights in this increase a numerical investigation has been undertaken with different strategies using ABAQUS and IMPETUS softwares in order to address quasi-static and dynamic loading conditions. Simulations were conducted with the ABAQUS software in order to carry out a comparative analysis of both implicit and explicit approaches. In addition to standard Finite Element Method (FEM) applied to quasi-static and dynamic conditions, the eXtended-Finite Element Method (X-FEM) was applied to quasistatic conditions. In both approaches, implicit and explicit, crack initiation and propagation were governed by a critical plastic strain threshold combined with a displacement-based damage evolution criterion. Simulations conducted with the IMPETUS software use an explicit approach and second order elements for both quasi-static and dynamic loading conditions. A node-splitting method using an energy-based damage criterion was employed to simulate the crack initiation and propagation. Experimental data and numerical results have been compared, allowing to determine the ability of these two softwares to simulate accurately three-point bend fracture tests.

The Influence of the Curved Transition on the Coach Roof Cross Beams in Rollover Crashworthiness

2011 ◽  
Vol 474-476 ◽  
pp. 1920-1925
Author(s):  
Fu Lin Shen ◽  
Jun Liang Jiu ◽  
Zhao Kai Li ◽  
Xu Liang Xie ◽  
Ying Hui Mao
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Energy Absorption ◽  
Collision Energy ◽  
Element Model ◽  
Finite Element Models ◽  
Complete Vehicle ◽  
Simulation Results ◽  
Survival Space ◽  
Peak Value

In order to improve the rollover crashworthiness of coach, three roof beam structures commonly used in coach were established with finite element models for the rollover simulation, then the energy absorption, acceleration and body pillar deformation were analyzed. The simulation results show that circle-curved transition and non-curved transition on the roof have better collision performance. Especially, the latter not only reduces the acceleration peak value, but also transfers more collision energy to the offside lateral. The whole coach body will be involved in deformation, thus, the intrusion of survival space would be reduced. Finally, the complete vehicle skeleton finite element model of a 6127-type high-bed coach was built, and the influences of circle-curved transition and non-curved transition on the roof in rollover test were analyzed.

Experimental study on quasi-static penetration process of cylindrical indenters with different nose shapes into the hybrid composite panels

2018 ◽  
Vol 53 (1) ◽  
pp. 107-123 ◽  
Author(s):  
Seyed Ahmad Taghizadeh ◽  
Gholamhossein Liaghat ◽  
Abbas Niknejad ◽  
Ehsan Pedram
Keyword(s):  
Energy Absorption ◽  
Hybrid Composite ◽  
Failure Modes ◽  
Peak Load ◽  
Composite Panels ◽  
Absorbed Energy ◽  
Penetration Process ◽  
Maximum Deformation ◽  
Static Penetration ◽  
Pull Out

The main aim of the present research is to investigate the quasi-static penetration process of cylindrical indenters with different nose shapes into multilayered composite panels made of Dyneema and Glass woven fibers, and aluminum face sheets. For better understanding of the perforation mechanism of the composite panels, effects of indenter geometry, stacking sequences, and boundary conditions are studied and their effects on energy absorption, specific absorbed energy, maximum deformation, peak load, and failure modes are evaluated and discussed. Samples with different layering configurations loaded under quasi-static punch and indentation with loading rate of 5 mm/min using universal testing machine and cylindrical rigid indenters with different nose shapes geometries consist of blunt, hemispherical, conical, and ogival. Regarding the boundary condition effects, two different rigid fixtures are designed and manufactured with the same external square perimeter (250 × 250 mm) and two different internal perimeters of circular and square shapes respectively, with diameter of 15 mm and edge side of 100 mm. Results show that the hybrid composite panels composed of Dyneema sheets, exhibits significantly better load carrying capacity and specific absorbed energy under both loading conditions. Indenter nose shape significantly affects elastic load, peak load, and energy absorption and maximum deformation. Furthermore, from visual observations based on digital microscopic images, fiber breakage, fiber pull out, intralaminar delamination, and debonding between the composite layers within the damage zone were inspected and recognized as the main damage mechanisms of panels. Output data obtained from all the experimental investigation were reported, discussed, and commented upon.

Analysis of a Liquid Filled Poroelastic Cylinder Exposed to a Time Varying Pressure Load

2017 ◽  
Author(s):  
Tyler L. Ceste ◽  
Sridhar Santhanam ◽  
Gerard F. Jones
Keyword(s):  
Finite Element ◽  
Porous Materials ◽  
Energy Absorption ◽  
Solid Phase ◽  
Dynamic Compression ◽  
Analytical Models ◽  
Finite Element Models ◽  
Porous Cylinder ◽  
Linear Effect ◽  
Non Linear

Porous materials are of interest for a number of applications one of them being energy absorption. These materials offer the ability to absorb more energy than a typical metallic solid and thus provide an opportunity to improve the performance of structures that endure blast loads. These structures undergo very large loads in very short periods of time and therefore maximizing energy absorption is paramount. This study seeks to improve the understanding of the response of porous materials by developing both analytical and finite element models for a liquid filled porous cylinder exposed to a dynamic compression loading. The poroelastic cylinder consists of a porous metallic solid phase and a viscous liquid phase. These two phases provide for two mechanisms of energy dissipation which are that of the deformation of the solid and the viscous flow of the liquid. The theories of elasticity and porous media were used to formulate the governing equations for the liquid filled porous cylinder. These equations describe the coupling between the displacements of the solid cylinder and the pressure distribution of the liquid. Analytical and finite element models were developed to predict the cylinders response in order to determine the amount of energy absorbed when the cylinder is exposed to a dynamic compression load. Analytical models were developed to validate the finite element results. As more complexity is added to this problem an analytical approach becomes unviable and a finite element approach must be used. One such complexity that can be considered is the effect of utilizing a non-constant liquid viscosity, which requires developing a non-linear finite element model to account for the viscositys dependence on strain rate. This added non-linear effect should allow for additional viscous energy to be absorbed and thus can further enhance the performance of the system.

Analysis of Brick Wall’s Failure Modes under Earthquake Effect

2012 ◽  
Vol 226-228 ◽  
pp. 1066-1071
Author(s):  
Kai Qin ◽  
Wen Fang Zhang ◽  
Li Jun Niu
Keyword(s):  
Finite Element ◽  
Failure Modes ◽  
Shear Failure ◽  
Brick Masonry ◽  
Width Ratio ◽  
Finite Element Models ◽  
Brick Wall ◽  
Flexural Failure ◽  
Earthquake Effect ◽  
Shear Bearing Capacity

Brick wall has large lateral sidesway stiffness and shear failure often occurs under horizontal earthquake effect, but the scourge surveys indicate that flexural failure can also occurs sometimes. Given that there are still few researches about masonry’s failure modes in China, Finite Element Models of non-reinforced brick masonry with different Depth-width Ratios and reinforced brick masonry whose Depth-width Ratio is 1.444 are established with the help of MSC.MARC to analyze its failure mode under horizontal action. The researching results indicate that: The larger the Depth-width Ratio of non-reinforced brick masonry is, the more flexural components it has and the better its ductility is; the smaller its Depth-width Ratio is, the larger the D-value of Bottom Shear and Ultimate Shear Bearing Capacity according to formulas from code before damage, and thereby the more easily the shear failure takes place; however, the ductility of brick wall’s flexural failure is improved evidently through making reasonable reinforcement schemes.

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