Quasi-static indentation characteristics of sandwich composites with hybrid facesheets: Experimental and numerical approach

2021 ◽  
pp. 109963622199387
Author(s):  
Subramani Anbazhagan ◽  
Periyasamy Manikandan ◽  
Gin B Chai ◽  
Sunil C Joshi
Keyword(s):  
Energy Absorption ◽  
Failure Modes ◽  
Volume Fraction ◽  
Numerical Models ◽  
Damage Model ◽  
Sandwich Panels ◽  
Numerical Approach ◽  
Metal Composite ◽  
Numerical Predictions ◽  
Static Indentation

The load response, energy absorption, different damage mechanisms and failure modes of sandwich panels subjected to complete perforation by quasi-static indentation and the insights gleaned are presented in this paper. The experimental campaign was carried out on samples made of different type of facesheets: Aluminium, glass fibre-reinforced plastic and metal-composite hybrid (combined aluminium and GFRP) with two different core heights. Reliable numerical models were developed with appropriate constitutive material and damage model for facesheets and honeycomb core to complement the experimental observations. Good agreement between experimental results and numerical predictions in terms of force-displacement response and perforation damage ensure the fidelity of the developed numerical model. Effects of facesheet type, core height, energy absorbed by the constituent layers, damage evolution history are briefly discussed. It was observed that the energy absorption of sandwich panels and peak indentation force resisted by the top and bottom facesheet are strongly dependent on its metal-volume fraction, whilst unaffected with the height of the core. Recommendations for developing computationally efficient numerical models were provided.

Evaluations of failure initiation criteria for predicting damages of composite structures under crushing loading

2018 ◽  
Vol 37 (21) ◽  
pp. 1279-1303 ◽  
Author(s):  
Hongyong Jiang ◽  
Yiru Ren ◽  
Zhihui Liu ◽  
Songjun Zhang ◽  
Xiaoqing Wang
Keyword(s):  
Composite Structures ◽  
Maximum Stress ◽  
Failure Modes ◽  
Damage Model ◽  
Axial Loading ◽  
Failure Criteria ◽  
Quantitative Relation ◽  
Stress Criterion ◽  
Failure Initiation ◽  
Numerical Predictions

The crushing behaviors of thin-walled composite structures subjected to quasi-static axial loading are comparatively evaluated using four different failure initiation criteria. Both available crushing tests of composite corrugated plate and square tube are used to validate the stiffness degradation-based damage model with the Maximum-stress criterion. Comparatively, Hashin, Maximum-stress, Stress-based Linde, and Modified criteria are respectively implemented in the damage model to predict crush behaviors of corrugated plate and square tube. To develop failure criteria, effects of shear coefficients and exponents in the Modified and Maximum-stress criteria on damage mechanisms of corrugated plate are discussed. Results show that numerical predictions successfully capture both of experimental failure modes and load–displacement responses. The Modified criterion and particularly Maximum-stress criterion are found to be more appropriate for present crush models of corrugated plate and square tube. When increasing the failure index, the crushing load is decreased, which also causes premature material failure. The shear coefficient and exponents have dramatic influence on the crushing load. Overall, an insight into the quantitative relation of failure initiation is obtained.

Low-velocity impact response of wood-strand sandwich panels and their components

Holzforschung ◽  
2018 ◽  
Vol 72 (8) ◽  
pp. 681-689 ◽  
Author(s):  
Mostafa Mohammadabadi ◽  
Vikram Yadama ◽  
LiHong Yao ◽  
Debes Bhattacharyya
Keyword(s):  
Energy Absorption ◽  
Impact Energy ◽  
Failure Modes ◽  
Sandwich Panels ◽  
Low Velocity Impact ◽  
Insulation Material ◽  
Low Velocity ◽  
Velocity Impact ◽  
Section Modulus ◽  
The Impact

AbstractProfiled hollow core sandwich panels (SPs) and their components (outer layers and core) were manufactured with ponderosa and lodgepole pine wood strands to determine the effects of low-velocity impact forces and to observe their energy absorption (EA) capacities and failure modes. An instrumented drop weight impact system was applied and the tests were performed by releasing the impact head from 500 mm for all the specimens while the impactors (IMPs) were equipped with hemispherical and flat head cylindrical heads. SPs with cavities filled with a rigid foam insulation material (SPfoam) were also tested to understand the change in EA behavior and failure mode. Failure modes induced by both IMPs to SPs were found to be splitting, perforating, penetrating, core crushing and debonding between the core and the outer layers. SPfoams absorbed 26% more energy than unfilled SPs. SPfoams with urethane foam suffer less severe failure modes than SPs. SPs in a ridge-loading configuration absorbed more impact energy than those in a valley-loading configuration, especially when impacted by a hemispherical IMP. Based on the results, it is evident that sandwich structure is more efficient than a solid panel concerning impact energy absorption, primarily due to a larger elastic section modulus of the core’s corrugated geometry.

Numerical Investigation on Impact Energy Absorption of Single-Walled Carbon Nanotube Reinforced Composites

2012 ◽  
Author(s):  
Lingyu Sun ◽  
Jian Zhang ◽  
Dingxin Leng
Keyword(s):  
Numerical Investigation ◽  
Energy Absorption ◽  
Impact Energy ◽  
Metal Matrix ◽  
Failure Modes ◽  
Volume Fraction ◽  
Matrix Material ◽  
Reinforced Composites ◽  
Alloy Matrix ◽  
The Impact

With the exceptional mechanical properties, carbon nanotubes (CNTs) are considered to be attractive candidate reinforcements for composite materials and to have potential applications in improving the energy absorption capability of matrix material. However, it is still difficult to reveal the micro-mechanisms of the impact energy absorption of CNT-reinforced composites by experiments, hence, the numerical investigation is helpful. In this paper, a unit cell of single-walled CNTs (SWCNTs) embedded in metal matrix is modeled by nano-scale finite element method. Under impact loads, the failure modes of a single SWCNT and the SWCNT in matrix are predicted, respectively, and several possible energy absorption mechanisms are explained and compared. The investigation shows that, the metal matrix restraints the radial expansion of the SWCNT and therefore improves its crush buckling resistance, and makes it absorb more energy before collapse. The specific energy absorption of SWCNTs-reinforce composites increases with the increasing volume fraction of SWCNTs in both matrixes, and ascends more quickly in magnesium alloy than in aluminum alloy matrix.

Notched Specimens Fracture Prediction with an Advanced GTN Model

2011 ◽  
Vol 488-489 ◽  
pp. 77-80
Author(s):  
Joseph Fansi ◽  
Mohamed Ben Bettaieb ◽  
Tudor Balan ◽  
Xavier Lemoine ◽  
Anne Marie Habraken
Keyword(s):  
Dual Phase Steel ◽  
Damage Model ◽  
Numerical Approach ◽  
Void Coalescence ◽  
Present Contribution ◽  
Notched Specimens ◽  
Numerical Predictions ◽  
Growth Laws ◽  
Gtn Damage Model ◽  
User Material Subroutine

This present contribution consists of implementing an advanced GTN damage model as a "User Material subroutine" in the Abaqus FE code. This damage model is based on specific nucleation and growth laws in order to predict the void coalescence properties of the material. When applied, this implementation predicts the damage evolution and the stress state of notched specimens made from dual phase steel. By comparing numerical predictions with experimental results, the numerical approach was improved and then validated.

Hydrodynamic Load Modeling for Offshore Free-Floating Macroalgal Aquaculture Under Extreme Environmental Conditions

2019 ◽  
Author(s):  
Ming Chen ◽  
Solomon C. Yim ◽  
Daniel Cox ◽  
Taiping Wang ◽  
Michael Huesemann ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Environmental Conditions ◽  
Failure Modes ◽  
Numerical Models ◽  
Farming System ◽  
Saccharina Latissima ◽  
Response Analysis ◽  
Hydrodynamic Load ◽  
Numerical Predictions ◽  
Long Line

Abstract This article describes a preliminary study of an on-going ARPA-E (Advanced Research Projects Agency-Energy) MARINER Phase I project. The hydrodynamic load and dynamic response of an innovative offshore macroalgae cultivation system, Nautical Offshore Macroalgal Autonomous Device (NOMAD), under extreme environmental conditions is examined. The high strength, extremely durable, recyclable carbon fiber (rCF) free-floating long-line is applied with polyculture (Nereocystis luetkeana (bull kelp) and Saccharina latissima (sugar kelp)) in the NOMAD system. This novel macroalgal farming system is designed to free float from Washington State to California along the west coast of the US to avoid anchoring costs and the failure of earlier offshore growth trials. In this study, we expect to identify possible failure modes for the preliminarily design of NOMAD free-floating long-line macroalgal farming system based on the preliminary numerical predictions. We developed a 1km system-scale NOMAD free-floating long-line numerical model and performed a dynamic response analysis on the long-line to determine the behaviors of the long-line under extreme environmental conditions. The 1km free-floating rCF long-line responses very flexible due to wave and current activities even for large bending stiffness. Therefore, the potential entanglement of free-floating long-line on a global scale may cause the system failure even when the tensions and bending moments are in the safe range. Three cases include 10m NOMAD free-floating long-line with sugar kelp, bull kelp, and polyculture numerical models are developed, and the simulation results are analyzed. The tensions at the holdfast of the kelps in these cases are found to be below the breakage limit approximately. However, the severe clumping of the kelps and potential entanglement of adjacent lines may result in damage to the farming system.

ORTHOTROPIC DAMAGE MODEL USING TSAI-WU FAILURE CRITERIA

2021 ◽  
Author(s):  
M. R. T. ARRUDA ◽  
L. ALMEIDA-FERNANDES, ◽  
L. CASTRO ◽  
J. R. CORREIA
Keyword(s):  
Failure Modes ◽  
Numerical Models ◽  
Equivalent Stress ◽  
Damage Model ◽  
Failure Criteria ◽  
Simple Method ◽  
Finite Element Software ◽  
User Subroutine ◽  
Novel Approach ◽  
The Moment

This paper presents a novel approach concerning the development of an orthotropic damage model, based on the original plane Tsai-Wu failure criteria. In its original formulation, the Tsai-Wu is a mode independent criterion only capable of acknowledging the existence of damage in a certain point of the material. It is not capable of identifying if the damage is located in the fiber, matrix or intralaminar zone. This work plans to fill this gap in knowledge by providing a simple method, based on equivalent stress and strains, that identifies the failure modes when the Tsai-Wu failure criteria is near the on-set of damage. Using this novel method, it is possible to implement classical damage evolutions constitutive laws based on the MTL formulation. At the moment the proposed damage formulation is based on plane stress space and Mode I fracture, but it is expected in the future to evolve in to a full 3D damage model. The damage model is implemented in the commercial finite element software ABAQUS using user-subroutine UMAT, and all numerical models are compared with the experimental results.

Rousselier Parameter Calibration for Esshete Weld Metal

2015 ◽  
Author(s):  
Sutham Arun ◽  
Andrew H. Sherry ◽  
Mohammad Sheikh ◽  
Mike C. Smith
Keyword(s):  
Fracture Toughness ◽  
Numerical Models ◽  
Damage Model ◽  
Mesh Size ◽  
Model Parameters ◽  
Fracture Toughness Test ◽  
Parameter Calibration ◽  
Numerical Predictions ◽  
Industrial Grade ◽  
Weld Material

This paper describes an investigation concerning calibration of the Rousselier ductile damage model parameters for an industrial grade weld material (Esshete 1250). Parameters such as σ1 and the mesh size (Lc) were calibrated using numerical models of tensile and fracture toughness test specimens (smooth round bar and side-grooved compact-tension (CT) types) and adopting the Rousselier damage model as a constitutive relation. The process of parameter calibration was investigated by comparing the numerical load-displacement, crack initiation and growth predictions with experimental data measured using the two test geometries. It was found that it was not possible to obtain a single set of parameters which provided a good agreement between numerical predictions and experimental behaviour for both smooth tensile bar and CT specimen due to the difference in the failure mechanism of these specimens. Therefore, experimental J-R curve data determined from unload-compliance CT laboratory specimen fracture toughness tests of Esshete weld material were used to determine the values of these two parameters. The calibration results showed that the values of σ1 affect the change of the slope of J-R curve, whereas an increase in Lc elevates the crack growth resistance. The ductile fracture behaviour of the weld material is best simulated using the value of Lc = 50 μm and σ1 = 506 MPa. A detailed description of the numerical approach and calibration steps undertaken are provided.

scholarly journals Application of an Advanced GTN Model

2012 ◽  
Author(s):  
Joseph Fansi ◽  
Anne-Marie Habraken ◽  
Tudor Balan ◽  
Xavier Lemoine ◽  
Caroline Landron ◽  
...  
Keyword(s):  
Dual Phase Steel ◽  
Damage Model ◽  
Numerical Approach ◽  
Present Contribution ◽  
Notched Specimens ◽  
Numerical Predictions ◽  
Growth Laws ◽  
Gtn Damage Model ◽  
User Material Subroutine ◽  
X Ray Absorption

The present contribution consists of implementing an advanced GTN damage model as a “User Material subroutine” in the Abaqus FE code. This damage model is based on specific nucleation and growth laws. This model is applied to the prediction of the damage evolution and the stress state in notched specimens made of dual phase steel. By comparing numerical predictions with experimental results based on high-resolution X-ray absorption tomography, the numerical approach was improved and validated.

scholarly journals Rock Pillar Design Using a Masonry Equivalent Numerical Model

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 890
Author(s):  
Ricardo Moffat ◽  
Cristian Caceres ◽  
Eugenia Tapia
Keyword(s):  
Rock Mass ◽  
Failure Modes ◽  
Underground Mining ◽  
Numerical Models ◽  
Numerical Approach ◽  
Practical Experience ◽  
Engineering Problem ◽  
Pillar Design ◽  
Rock Pillar ◽  
Rock Pillars

In underground mining, the design of rock pillars is of crucial importance as these are structures that allow safe mining by maintaining the stability of the surrounding excavations. Pillar design is often a complex task, as it involves estimating the loads at depths and the strength of the rock mass fabric, which depend on the intact strength of the rock and the shape of the pillar in terms of the aspect ratio (width/height). The design also depends on the number, persistence, orientation, and strength of the discontinuities with respect to the orientation and magnitude of the stresses present. Solutions to this engineering problem are based on one or more of the following approaches: empirical design methods, practical experience, and/or numerical modeling. Based on the similarities between masonry structures and rock mass characteristics, an equivalent approach is proposed as the one commonly used in masonry but applied to rock pillar design. Numerical models using different geometric configurations and state of stresses are carried out using a finite difference numerical approach with an adapted masonry model applied to rocks. The results show the capability of the numerical approach to replicate common types of pillar failure modes and stability thresholds as those observed in practice.

Energy absorption and damage mechanism of UHMWPE-aluminum composite sandwich laminate under impact loading: An experimental investigation

2021 ◽  
pp. 109963622110204
Author(s):  
Hassan Mansoori ◽  
Mahnaz Zakeri ◽  
Mario Guagliano
Keyword(s):  
Energy Absorption ◽  
Failure Modes ◽  
Volume Fraction ◽  
Fiber Composite ◽  
Damage Mechanism ◽  
Impact Behavior ◽  
Aluminum Composite ◽  
Uhmwpe Fiber ◽  
Fiber Metal Laminate ◽  
Fiber Metal

This study investigates impact behavior and energy absorption of a Fiber Metal Laminate (FML) made of ultra-high molecular weight polyethylene (UHMWPE) fiber composite and aluminum 2024-T3 sheets. Specimens have been tested against two types of projectiles and failure modes are compared. The effect of different thicknesses of aluminum sheets and composite core on impact performance is investigated. To examine the influence of the lay-up sequence, two types of FML including 2/1 and 3/2 configurations have been tested. The results show that increasing the thickness of the composite core increases the absorption of energy as well as specific energy absorption (SEA). The highest amount of SEA is obtained for the sample with the lowest metal volume fraction. Damage patterns show that due to the flexibility of UHMWPE fibers and ductility of Al 2024-T3, the metal and the composite core have been deformed proportionally and more energy is absorbed. This mechanism is not seen in other conventional FMLs such as glass fiber metal laminate (GLARE). Compared with aluminum sheet and GLARE under the same conditions, the proposed FML has SEA more than 3 times that of aluminum and more than 2 times that of GLARE.

Sign in / Sign up

Export Citation Format

Share Document