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# Composite Structures - Science topic

Explore the latest questions and answers in Composite Structures, and find Composite Structures experts.

Questions related to Composite Structures

**Are layered composites and structural composites different?**

The idea is to make a repair in a composite panel but i cannot find any properties like Ftu, Fcu, etc like in metals. We need to be conservative in this case where can i find values for composites structures?

I have a 3D orthogonal woven composite structure with warp, weft, and binder yarns oriented in three directions. After modeling these yarns, I imported them into Abaqus as parts. I modeled the yarns as solid elements and assigned their material properties, including elastic, density, and Hashin damage properties, to each section. For meshing, I used C3D8R elements for each yarn. I set up the appropriate impact conditions. However, I am encountering an issue with the Hashin damage model. In Abaqus, I consistently receive the error message: "Hashin damage initiation criteria cannot be used with element 1 instance binderyarn-1-1."

Could you suggest any strategies to model this using the Hashin criteria without implementing a UMAT subroutine? How can I resolve this issue?

I've conducted FE analysis of composite structure as shown figure. However, the strain on the metal surface does not match the experimental values. I am new to FEM and I am having trouble understanding the cause of this. Interface1 is applied friction coefficient of 0.7, and Interface2 is applied friction coefficient of 0.3. I use Ansys mechanical.

Please accept my apologies for my poor English.

I use Abaqus for dynamic analysis of composite structures. In Abaqus, the damping can be defined at a material/element level and global level in the analysis. I am confused about the structural damping part in Abaqus and the damping at the material level as described below.

In the global level, the Rayleigh damping is Del = alpha x M + beta x K and the Structural Damping will modify the global stiffness matrix by a factor 's' where the stiffness matrix will be Ks=sK. 's' is the structural damping factor.

According to many textbooks, they take into account the effect of the structural damping by assuming an equivalent viscous damping ratio which could be added to the one from material damping when calculating the alpha and beta values in the Rayleigh Damping model.

In the material level, the number of elements, volume, and density of the elements alongside the alpha and beta values determine the damping matrix. I wonder if the alpha and beta values are the same as the global ones. I suspect they will be different because in the global level, the natural frequency and damping ratio of the entire model are used to calculate the alpha and beta values.

Your advice on these issues is highly appreciated.

I wanna make a composite structure including two oxide minerals, in common surface in materials studio software.

Hypersonic vehicles, which travel at speeds greater than Mach 5, experience extreme thermal and mechanical loads during flight. The objective of this research is to investigate the behavior of composite materials at different length scales, ranging from the microstructure of individual fibers to the macroscopic behavior of the composite structure, under hypersonic conditions. The research would involve developing advanced computational models and simulation techniques to predict the mechanical response, thermal behavior, and failure mechanisms of composite materials in hypersonic environments.

I'm working on my thesis about reliability analysis of composite structures. Can I use maximum deflection of the plate structure as failure criteria to define limit state function to perform reliability analysis or I should use conventional failure criteria's (i.e. Tsai-Wu criteria)

I have submitted my manuscript to Steel and Composite Structures Journal two days ago. However, until now, I have not received a confirmation email from this journal. At the end of the submission steps, it was written that "Congratulations! Your Submission has been completed!"

Is this normal? What should I do now?

Myself Nekin Joshua R, Research scholar from Vellore Institute of Technology(VIT), Vellore. I need a drop weight testing facility.

Please let me know where it is available in India ( Preferably nearer to Tamilnadu and also suggest the testing facility all over india).

The question asks for a description of what information can be obtained from High Performance Liquid Chromatography (HPLC) data regarding milk oligosaccharides. The answer to this question may include details about the composition, structure, and concentration of milk oligosaccharides that can be analyzed through HPLC.

Myself Nekin Joshua R. I like to do my research in Biomimic structures like Nacre, Auxetic, Conch Shell, Hexagonal cellular structure, Hourglass structure, Bouligand Structure.

And 3D print the structures in FDM and like to test the mechanical properties, Ballistic performance, Impact test.

**I need to select any one bimimic structure and need to analyze**. Please help me to identify which one structure has more energy absorbing property and Armor applications.

Please tell me which one structure I can select.

I study the delamination of laminates upper and bottom skins of honeycomb composite structure simple supported from two sides and under bending stress.

I consider the developed tension on the bottom skin as the main peeling force that cause delamination.

Is my thinking correct?

Also, do you suggest textbooks?

Hi everyone

I want to compare a monolithic polymer composite sample and a 3D-printed polymer composite sample. However, I need some references for this matter. Any contribution would be appreciated, kindly.

Consider a composite fluid-conveying pipe with two equal-length spans. Using the "Oke et al. (2018) Composite structure" for single-span composite fluid-conveying pipe, I computed the "EI" mass of pipe and fluid values. But now I'd want to figure out the stiffness and masses of a two-span fluid conveying pipe with an equal length of 1 metre.

Is there any literature on multi-span composite fluid-conveying pipe calculations?

Mechanical engineering researchers who want to collaborate in writing ISI papers in the fields of vibrations, nonlinear vibration, plates, shells, and composite structures can send me a message on LinkedIn.
If you wish, check out my recent articles at the link below:

What does PPA stand for in the sentence "Diaphragm forming (also referred to as hot drape forming) is one potential method for automating the production of low cost preforms for high volume applications (30,000+

**ppa**), due to lower capital investment compared to matched-tool forming." in the paper**Double diaphragm forming simulation for complex composite structures**?Thank you a lot.

Hi all,

I have a problem in defining contact. There is a 3D composite wall model . I have used Surface to Surface contact. I receive these errors:

1-There are 3 unconnected regions in the model.

2-There is zero FORCE everywhere in the model based on the default criterion. please check the value of the average FORCE during the current iteration to verify that the FORCE is small enough to be treated as zero. if not, please use the solution controls to reset the criterion for zero FORCE.

Any idea is appreciated

Regards

Mahya

I need to know the online platforms available for submitting papers related to composite structure design and its study.

Since I am planning to submit for the first time, I need to know the formats and guidelines for the submitting papers online.

We fabricated the composite of PVA and nano-carbon-particles. The results of zeta sizer show that the size of PVA chains is increased and nano-carbon serves as a crosslinker. But in the case of rheometer's results, the viscosity of the above sample is decreased, which shows that nano-carbon serves as surfactant. The mechanical properties of composite structure are enhanced and XRD shows that the crystalline regions are less in the composite structure. What could be the possible reason of decrease in viscosity in your opinion ?

Here i have attached some XRD, zeta sizer and rheometer results..

Hello Researchers,

In the literature pertaining to sandwich panels, we often come across terms like "sandwich panels with a stiff core" and "sandwich panels with a soft core". How do we formally differentiate between these two? While the name itself suggests that for a stiff core the ratio of the shear modulus of the core to that of the face sheet is higher than the same ratio for a soft core. But is there any well-defined condition wherein which we can differentiate between a sandwich panel having a stiff core and one having a soft core?

I would also appreciate your suggestions/corrections on another point. As per my understanding for a stiff core, equivalent single layer theories based on FSDT or Reddy's Third Order Theory may give sufficiently accurate results. But for a soft core, refined higher-order theories usually with layerwise displacement assumption may be required for an accurate analysis.

I am trying to model a reinforced concrete structure strengthened with CFRP bar. Could you please kindly tell me the key points to modeling CFRP bar? How do you define its material properties? Any help will be highly appreciated!

I am attempting to make a microscale RVE for composite structures using the M-T method. I am currently utilising MatLab to do so in two dimensions. However, I would like some further guidance on implementing the M-T method in Python. I would also like to progress the model into three dimensions and create a time-dependent continuum damage process.

Thanks

Is it possible to do a multivariate analysis from a compositional statistical analysis perspective?

Without excluding measurements outside the compositional structure of a substance such as T C°,pH,EC...etc , Or are there conditions and restrictions for that?

i searched many theoretical research paper but I cant find it

I'm planning to perform a low-velocity impact analysis on a sandwich composite consisting of top and bottom face sheets (Unidirectional fibre reinforced) with 4 plies each and a core (aluminium). The thicknesses are small relative to the other dimensions. After going through various materials, I'm still confused whether which one among the following combinations of elements I should go for -

1) SC8R (Core and face sheets)

2) SC8R (Core) and C3D8R (Face sheets)

3) SC8R (Face sheets) and C3D8R (Core)

4) C3D8R (Core and face sheets)

SC8R - Continuum Shell Element

C3D8R - Solid Element

Any suggestions on how to define local coordinate system (LCS) in APDL for shell elements (SHELL 181) meshed on hemi-spherical surface.

All the elements throughout the hemispherical surface should have one reference orientation so that I can define fibre orientation in each layer with respect to one axis of element? I had implemented the procedure of example 3.9 from text book "Finite Element Analysis of Composite Materials Using ANSYS by Ever J. Barbero".

I modelled part of sphere (45 degress anle) and used Local Cartesian Coordinate System at Origin for elements meshed on the spherical surface but unable to get same element orientation for all the elements on the hemispherical surface.I am attaching the APDL code and the image of generated mesh.

I tried by defining different coordinate systems but unable to get certain fixed orienation for all elements on the spherical surface.

The purpose of this apdl code is to build FE model for designing Type 4 COPV (COMPOSITE OVERWRAPPED SPHERICLE PRESSURE VESSEL)

Please help me how to define orientation of fibers over the sphericle surface using SHELL 181 element.

Hello All!

I am trying to model a composite in Abaqus, and specifically trying to capture the fiber realignment on loading.

One of the approaches I am considering is to.homogenise the fiber layer, and define anisotropic material properties that rotate on loading. This coordinate system should rotate following the direction of a prescribed edge of each element.

What would be the best way to model this rotating material orientation?

Hello everyone,

I am trying to model a DCB (mode-1) test for a carbon-fiber composite sample. However, I am a bit confused since I am very new to modelling and ABAQUS so I am looking for some help.

For composite structures, it is said that cohesive zone method is one of the best choice to model the initial crack area but in our experiments, we used a teflon film as crack initiator. That's why I am a bit confused. How could I model this teflon film in ABAQUS? Should I model it as a cohesive element with some values that I found on literature ? Does the element/material of the crack area has an effect on results ?

Any help would be appreciated. Thank you very much.

I modeled a concrete deck slab on top of steel girders in ANSYS APDL

but my results for the bending stress (X component stress) from ANSYS do not match what I obtained from hand calculations Using Mc / I

using Mc / I i obtained 29 MPa

and from ANSYS i got 10 MPa

i attached below my calculation as well as my model and elements used.

i used MPC184 rigid link to connect between the concrete deck slab shell element and top flange steel girder.

the slab is simply supported (roller and pin)

any idea what might be wrong?

When can the Classical Laminate Theory (CLT) be applied in practice for analyzing composite laminates. I mean, under what conditions is it allowed to approximate the composite structure to be a lamina and hence, mathematically analyze and treat it as such? Can a composite airfoil be treated using CLT?

I have inventory data set of vascular plants using systematic distribution and two data sets for large mammal species, 1. camera trap data set and 2. rangers' SMART patrol data set. My objectives are;

1. to find relationship between species richness of vascular plants and large mammals

2. to compare distribution of 3 herbivores in different species richness of vascular plants and forest composition (structure, density, canopy coverage, etc.)

Dear All,

*I am currently conducting parametric studies on Concrete Filled Double Skin Tubes(CFDST) in Abaqus. In case you are not familiar with CFDST, it is a composite structure with an outer steel tube and inner steel tube with a concrete sandwich in between them.*

**Introduction:****The problem:**I am using Abaqus Riks to conduct a parametric studies which involve bending of large tapered cantilever CFDST. I have done validation against smaller scale experimental specimen which are available in the literature. The validation worked very well for me, but when I changed the size of the structure then Abaqus Riks will encounter severe convergence difficulties.

**Diagnosis and attempts to solve the problem:**I believe the problem is with the interaction between the steel and concrete especially when concrete fails in tension which occurs early in the analysis typically less than 10% of the ultimate load. I have tried numerous things such as modifying the concrete model in tension(e.g. inputting elastoplastic definition of concrete in tension with a small tensile strength), trying different techniques with interactions,changing element and mesh type, changing the solver settings, and I have thoroughly checked the model many times.

I also tried inputting a small value for the viscosity parameter in the Concrete model in Abaqus. This would make the model work, but the results are very wrong where the bending capacity of the structure becomes much larger than it should be.

**Preliminary solution**: I have decided to eliminate interactions given they are the source of the problems, so I used TIES to model the interface between the steel and concrete. The model worked very well up to failure with no problems. Hence, this verifies that interactions are the source of the problem. TIES imply that there is a perfect bond between the steel and concrete. I believe this is a reasonable assumption because I am mainly interested in the global behaviour of the structure.

Besides, researchers in the past reported that different coefficient of frictions have a minor effect on the prediction capacity CFST and CFDST. Also, EC4 and AISC assume perfect bond when calculating the bending capacity of composite sections. Hence, this justifies assumption of perfect bond is a reasonable assumption which is actually adopted by many researchers simulating reinforced concrete structures.

**Conclusion:**I appreciate if you can mention any suggestion or solutions to solve this problem. Please note that I am avoiding to use Abaqus/Explicit because it may give inaccurate results for a static analysis due to various issues not to mention the very long time it would take to finish the simulation. Apologies if you found this post long.However, I made it as short as possible to explain this complicated problem which is happening for a really long time.

**How composites can be modeled in ANSYS Using Solid185?**

If one try to model a fiber composite layer bonded to a concrete beam for example using solid185 element in ANSY, this layer shall be modeled as volume, since solid185 is a brick element not a shell element. My question is: if thickness of this layer is only 1mm for example; shall we model this layer as a volume with (length x width x 1 mm) dimensions? OR shall we go to (shell section) menu (available in ANSYS) and input the thickness of the layer regardless the thickness of the layer in the modeled volume? OR shall we use both of them?

Thanks in advance.

I am planning to use the

**Discrete Element Method**for**propagation of Fracture**in**Reinforced concrete Structures**. Which book would be the best start to study**Discrete Element Method**from the beginning?Currently, I think functional and high filler content polymer nanocomposites are the current trend. Please let me know your thought.

Considering two

**composite**beams jointed to each other, for example by bolts, which are under**vibration**with**, what is the relation between the***different frequencies***temperature value**of contact surfaces and loosening between surfaces? By applying more torque on bolts and as a result, more pressure between two contact surfaces, which scenario could be expected: the surfaces' temperature resulted from vibration will**or***increase***?***decrease*And, what about the

**natural frequencies**?hello every one

i m working on delamination buckling analysis in abaqus 6.14...

now i want to add geometric imperfection in my model while i m using general static step for buckling analysis ,,,

can any one help me how i can add geometric imperfection in my model

i don't perform eigen value analysis because i dont need different modes and their buckling load..

i just apply axial displacemnt on two parts joined by cohesive element with delamination between them....but now i want to add imperfection to it too..i have studied in the abaqus documentation how to add imperfection but that require eigen value analysis,,which i dont want

i just need to know if there is any other way to add imperfection to my model since i m using general static step..

thank u

best regards

hello dear scholars ,

i am looking for papers proving if abacus has failed crack growth simulation of bonded joints or delamination in composite structures?

my question is concerning the program itself not the model used in the experiment ( CZM, VCCT....)

Dear community,

for my master’s thesis I’ve been using the "Damage Evolution Law" feature available in ANSYS to calculate the failure behavior of FRP composite structures using FEM simulation. Within the Damage Evolution Law, two different options are available:

- Material Property Degradation

- Continuum Damage Mechanics

Right now I’m trying to figure out on which theoretical approach the two models are based. Could you provide a reference to the research papers in which the respective approaches were developed? Unfortunately, I could not find such a bibliography in either the Theory Reference or the Material Reference.

Many thanks in advance.

Part of the submission process to Composite Structures is to propose potential reviewers for the submitted paper. The reviewers and their contact information will be provided online during the submission. So, is it necessary to include the suggested reviewers in the cover letter with their contact information?

I made some impedance measurements under magnetic field to characterize magnetoelectric coupling on BTO-CFO composites. I can determine magnetoelectric coefficient by calculating dE/dH from obtained data.. i just don't know if such coefficient is enough reliable to report it in an article.

reviews on plant cell wall structure, composition and function

1. May i know the values for the concrete damaged plasticity in abaqus? it is default value or depends on the concrete properties? btw, where to obtain the values?

2. In the real case, there are the spreader beams on top of the concrete slab as the load inputs. may i know how to input this load in simulation analysis of ABAQUS? it should be assigned as line load/point load/...?

3. how to create the nonlinear result? which module should be used for assigning the nonlinear properties?

i am doing a research on composite structures (steel beam-concrete slab). Thank you for your time.

I modeled a composite plate in Geometry module, then meshed in model, but error comes while edit in setup module in ACP. Error box attached here.

I am trying to model a composite sandwich structure undergoing a typical drop weight impact test, for my final year project. I have no experience on Abaqus and there is not a lot of help available to me on this software. I have tried to follow YouTube videos to get an understanding of how to use the software; but I still lack the necessary skills.

Does anyone have any links to tutorials that would help me practice impact modelling on composites.

Any help would be greatly appreciated.

I have an one question which is :

What is a difference o relationship between layer-wise and zig-zag theories.

I have got a publication in which the authors prepared BaFe

_{12}O_{19}/CoFe_{2}O_{4}. But the amount / concentration used for preparing the metal nitrate solutions were not mentioned in the publication (except mentioning 'stoichiometric ratio')in Materials and methods section.Please give your ideas about how to find the weight and concentration of the chemicals used in the synthesis from paper. Attaching the full paper with this question.

Reference:

Yang H, Liu M, Lin Y, Yang Y. Simultaneous enhancements of remanence and (BH) max in BaFe12O19/CoFe2O4 nanocomposite powders. Journal of Alloys and Compounds. 2015 May 15;631:335-9.

How much dead weight (load/pressure) are used to remove excess resin present in composite structure when using hand layup composite manufacturing techniques small lab.

I am looking to start working with the isogeometric method to analyze mechanical behavior such as beam, plate, shell and other structures of complex shapes.

can you help me by giving me simple examples in this method and with articles and books that have explanations and applications?

what do you suggest to me and thank you in advance?

CZone add-on in Abaqus 2016 forces the user to use a contact pair interaction (surface-to-surface), rather than a much easier general contact, between my crashbox (composite structure modelled with shell elements) and my barrier (rigid elements).

When I do this I get a strange behaviour and I do not understand where it comes from: the crashbox passes through the rigid barrier, "desintegrating", like in a cheese grater or something.

Any help would be appreciated. The input file and output image attached.

¿Does the urban development planning takes into account the generation of biological corridors that allow the transit of nativenative and and migratory species and their minimum survival requirements?

It is easy to deign a homogeneous 3D model of composite for an structural analysis. 3D models created using SOLID WORKS, CREO etc., are homogeneous models, even 3D models created using powerful FEM packages like ANSYS and ABAQUS are homogeneous possessing homogeneous structural property. What is the best software for creating a heterogeneous composite structure for structural analysis.

if we optical microscope, then what are points to observed?

it shows an error

1.adaptive meshing is not supported in any elements in this domain.

2.adaptive meshing contraints can be specified on adaptive mesh domain.

hi

i am working on simulation of air-couple ultrasonic wave propagation into the composite structure in Abaqus and investigate the behavior of delamination in composite.

I was wondering if any one can help me , How can i simulate Air in Abaqus in which i can propagate ultrasonic waves into the model?

also , how can i simulate delamination in composite?

THANK YOU

Which popular material used in the construction industry is a composite?

I am working on dyes removal from aqueous solution by using LDH. already there are alot of LDHs used regarding to this application. I want to bring novality by changing the structure and composition of LDH.

'Hello Everyone ,

Hope you are doing fine . I am a graduate student and I have not much idea of the scientific journals .

Can you suggest me some authentic journals where I could submit my work related to composite's structural (numerical investigation of buckling behavior) . The work is pure simulation based .

As I am a student I would really appreciate a journal with minimum to zero submission fee .

Best Regards

Aamir

I am searching for a good topic in Dynamic RAM for my research practice/project in VLSI Design domain. I want to work on outer peripheral circuitry for low power applications (Not into device level i.e structure and composition ).

I am doing buckling analysis of laminated composite shells with different cutouts under axial compression in abaqus . As a shell has different type of geometrical imperfection how can I introduce them separately in abaqus ?

I would like to ask you about a problem I have encountered. How could I define the elastic modulus in radial direction in terms of rectilinear orthotropic properties such as Ex and Ey. Similarly, I would like to write Etheta in terms of Ex, Ey and theta. Is there a way to transform rectilinear material properties into polar orthotropy ?

papers on petrographic, structural and physical properties of volcanic glass.

As part of my research for my PhD project, I wish to produce a FEA model of a bi-stable composite structure with piezoelectric transducers attached to the surface of the structure and optimize the system for maximum power output under certain dynamic load cases.

I am attempting to create the FEA model in ABAQUS. I understand the software doesn't provide a direct way to model a full electro-mechanical system (simulation of electrical circuit attached to piezoelectric transducers), unlike ANSYS, and so I would like to know whether a method exists to model a full electro-mechanical system in ABAQUS? If so, how is this method implemented?

It is about the types on nano particles that used in order to reinforcement of composite structures

Hello Everyone,

I need to modify and make a change for the composite materials and make it act in a different behavior so i am asking if anyone have/ or know a published data for the composite structures experimental set up in details! Just tell and i really appreciate your time you gave to me.

Thanks in advance

I want to start working on the generalized differential quadrature (GDQ) method to solve the problem of the mechanical behavior of beams, plates and shells.

Dear colleagues, I hope to give some suggestions (papers, books, etc.) and simple examples for work on this method.

I want to start working on the generalized differential quadrature (GDQ) method to solve the problem of the mechanical behavior of the beams, the plates and the shells.

Dear colleagues , I hope to give some suggestions (papers, books, etc.) and simple examples for work on this method.

Kindlya can any one tell me

it is possible to use the same laws of thin metallic structures

for the composite material

I am trying to model a composite material with periodic microstructure. I am trying to use the approach presented by Feyel (FE2 multiscale). it seems however a bit challenging to write a MATLAB code for the periodic homogenization theory (There is also no available codes). Therefore, I am seeking an initial guide to write a MATLAB code addresses my composite structure.

Thanks in advance!

My question is, should´nt the load induction lenght be in function of load conditions and not the geometric properties.

I am not an expert on this particular topic, so does anybody knows the theory of this load induction lenght or where can i find documentation about it.

I have 3 4th order non-linear Partial Differential Equations with three dependent variables and 2 independent variables. I have boundary conditions for 2 dependent variables. The problem is formulated when analysing a laminated composite structure. It is a steady-state analysis. Should I proceed with Navier's method/FEM/ or some other approach? I would appreciate suggestions. Thank you.

I have modeled a steel-concrete composite box girder in ABAQUS using following element type:

Steel box girder- S4R, Shear Connector(Stud)- C3D8R, Concrete Slab- C3D8R, reinforcement- T3D2

I have considered elastic and plastic behavior of both steel and concrete(CDP). While comparing load-deflection curve from both experiment and FEA, it has given me pretty much accurate value for ultimate load. However, the elastic response of the structure is much more stiffer from experiment data. I have already updated the FE model based on constructed specimen such as thickness of steel plate, steel & concrete strength. What could be the problem?