Science topic

# Elasticity - Science topic

Resistance and recovery from distortion of shape.

Questions related to Elasticity

Hi everyone,

I ran a model in my ABAQUS CAE, however, when the simulation finished, the elastic modulus of the model appear to be higher that the elastic modulus of the material that I had assigned. Is this possible and what factors that affect the model to behave in such ways? Thank you in advance.

I am trying to simulate low velocity impact on composite plates and every time I run the program it terminates and gives me this error. I am using MAT_ORTHOTROPIC_ELASTIC. Also, trying to understand the ABC directions. I understand that to get B you cross A into C. Do I define what I want ABC to be or does ABC direction correlate to XYZ?

We're looking for a plugin for FIJ or ImageJ that could help us to quantificate the amount of elastic fibres in a tissues like aortha stained with orcein, but couldn't find any by now.

Thank you

Hello all,

I am currently dealing with Abaqus and python and would like to solve the problem:

Since different geometries and different materials are considered, the Rp02 value of each material is used as a unit to keep the equivalent elastic-plastic stresses in a similar range, and the load range for the analysis has been set from 1*Rp02 to about 2.5*Rp02 for all different geometries and materials. Furthermore, the entire load range is divided into 6 load levels, as shown in the figure, and the equivalent elastic-plastic, and the corresponding equivalent elastic stress at each

load level is calculated.

How can I implement this with Python so that when I run the script in Abaqus, the loads are divided into 6 levels and between 1*Rp02 to about 2.5*Rp02?

I would be very pleased to receive your answer

Hello everyone,

I'm trying to calculate the elastic modulus tensor for a glass system based on MD simulation results. So far I believe I don't have any problem with Born term cB and I'm calculating it right :) but I am struggling with the stress fluctuation term cF. Has anyone here any experience with calculating elastic modulus tensor? Then I can explain into details what is the problem ...

Thanks

explain to me the parameters that can influence the acoustic and elastic properties of materials

Hello,

I am working on a laterally loaded H-pile and trying to model it in Plaxis 2D. I am having difficulty converting the 3D to an equivalent 2D pile with the same elastic and flexural properties. any suggestion about which element I can use (ex: plate, embedded beam ) and any advice regarding the Parameters? and would be appreciated if there are any helpful resources for modeling such a system.

thanks

Hello,

I am writing my thesis and I need to create a material database in a CAD program. I need to find a way to count mechanical properties of quasi-isotropic fiber laminates. I have found an algorythm to count elastic modulus and tensile strength but I need to know how the material would behave during twisting, too. How can I count Kirchoff' modulus or Poisson's ratio?

Please, help me.

I tried to perform tensile test in Deform 3D software but I faced some problems. Let me tell step by step.

Inputs given in tensile tests are

1. Elastic properties, 2. Plastic properties (Stress strain graph), 3. Failure criteria (Cockroft and latham failure criteria)

I have made one side (face) of tensile sample fixed and applied a constant velocity on the other side (opposite face) same as in experiment. I observed that very little thinning occurred near the opposite face where velocity was applied which was not matching with the experimental one (actually, failure location is close to centre). Also, No Effective strain contour generated during the simulation. Can anybody help me out in this ??

Consider this as urgent.

Hello my dear researchers

I use the elast package in wien2k and castep/materials studio to calculate the elastic constants of solids. I have a material with cubic structure, I make it a 2x1x1 supercell, so it becomes like tetragonal. My question is: to calculate the elastic constants, should I use the commands for cubic structure (C_set_elast_lapw) or those for tetragonal structure (T_set_elast_lapw).

And thanks in advance.

Hi all,

I am trying to model a joint connecting 1D BEAM elements using ABAQUS connector element with the joint behaviour obtained in a separate 3D analysis. For example, I have a joint modelled in 3D SHELL element and after analysing this joint I obtained a moment-rotation relationship of this 3D joint. This moment-rotation relationship is then assigned to an ABAQUS connector element connecting the 1D BEAM elements in the 1D BEAM model.

My question is how do you correctly define the elastic and plastic range of behaviour in ABAQUS connector element?

1. Is the Elastic behaviour option only for the elastic range of my moment-rotation relationship or do I have to define the full elastic-plastic range in this behaviour option? If the latter is correct, I then need to tell ABAQUS in the Plastic behaviour option from what moment onwards in the full elastic-plastic range defined in the Elastic behaviour option where it should behave plastically?

2. I tried to define negative values in the Plastic behaviour option as my joint can have load reversal, however, it keeps giving me error. Is the Plastic behaviour option only allow positive values? If so is that mean ABAQUS assumed the onset of plasticity occurs at the absolute value of the number I specified for both directions? What if the onset of plasticity of my joint is different in 2 loading directions? Do I need 2 separate Plasticity behaviour options (1 for each direction) for it to work?

I know this is a long question, hopefully, there is someone out there who read through this and could provide me with some direction.

Many thanks,

Heng

Hello!

Biot poroelasticity describes elastic deformation coupled to fluid flow, the flow is transient. I assume one can also consider the steady-state case. Are problems of this type relevant? Transient problems can be more practical, like: "A well works for 1 year pumping with fixed rate, what stress does it induce?", while I can't think of steady-state analogues. Or are there any?

Thanks in advance!

Hello, I need help getting a code in python or Fortran for elastic stiffness to calculate the shear modulus at varying mean effective stress by the Hardin formula in Abaqus. Can anyone help regarding this, or else from where I can learn to code?

Regards,

Manisha

Hello everyone,

I've written a rather simple linear elastic UMAT for orthotropic materials. I found that my output stresses are different from stresses should be.

For example:

In my model, I set a max load of 25 MPa and min load of 2.5 MPa (aka cyclic load ratio R=0.1). In my UMAT a wrote a line "write(*,*) "stress(2)=", stress(2) " to see how applied load matches outputs. I expect see alternation of 25 and 2.5 (when increment time=0.5), but I see the following:

stress(2)=0 - okay, initial step

...

stress(2)=-25 - okay

...

stress(2)=-49.99 ????

...

stress(2)=-2.5 - okay

...

stress(2)=-19.99 ????

then everything repeats

But in ABAQUS visualization stresses are as I set, 25 2.5 ...

Have you seen something similar? I'm bit confused, don't understand how it works.

If you have any ideas what can be wrong, let me know.

I have attached the UMAT subroutine file and inp file. Thank you.

Dear all, I'm applying a given load to a spring. After compressing the spring, I will lock it to prevent any movement, and I will remove the load source. How can I estimate the load loss that will inevitably and gradually happen with time (elastic potential energy dissipation from the spring in an enclosed system)?

Could anyone explain the difference between a linear elastic and linear viscous element?

also the meaning of parasitic viscous damping in an isolation system that results in a reduction of isolation system displacement demands

Good morning, greetings from Peru. I have a question. How is the critical elastic buckling load of a building calculated in Etabs or SAP 2000?

I know how to plot Force versus total story drift hysteresis curve but I dont know how to subtract elastic part. I have attached a picture that clarifies my question.

Hello fellow abaqus users,

I try to solve the following problem:

I have 3 solid bodies (please see the attached file). The bodies are tied to their respective neighbor. Loads to be applied are a thermal load (thermal expansion) and a rotational load around the Z-Axis. The steel body is encastred.

I tried to model the adhesive as cohesive elements with elastic behavior type traction, but were not able to combine this element type with the thermal expansion. Is this even possible? If not, is there a workaround? I am really looking forward to any tips and hints.

Thanks in advance,

Adam

- Knowing that the Mathematical elastic model does not admit no analytical solutions. I would like to know, is there are some specific techniques for validation of the solutions for anisotropic linear elastic model, particularly analyticly, or with some numerical simulations.

Hi..all,

I have a horizontal beam(BEAM188) having length of 1m, cross-section area of BxH = 0.02mx0.025m. UDL (1 unit) is applied on horizontal beam. This beam ends are supported by concrete/steel foundation having the area of cross-section of 0.02mx0.025 and its vertical height is 0.05m.

Now, If the supporting structure having some flexibility then how can we include the foundation stiffness (N/m^3) for the supporting system in ANSYS APDL GUI/Command prompt?

Kindly, someone can give inputs here?

For thermal contact conductance estimation, selection of plastic or elastic deformation models is based on plasticity index. At lower pressure at the interface, the deformation of surfaces may be elastic even though the plasticity index is greater than 1. Plasticity index will not account for pressure.

Hello,

I'm havaing difficulty understanding the

**relationship between crystalline properties and mechanical properties of polymers**.I'm compounding two biodegradable semi-crystalline polymer 1) PLA and 2)PBAT.

I analyzed DSC, TGA, XRD, and mechanical properties of above polymers and have a couple of questions.

1) Through XRD analysis, PLA turned out to be amorphous while PBAT has crystalline dimensions. but it is known that these two polymers are semi-crystalline polymers(both have melting point, crystallization point in DSC analysis). Then why PLA is amophous in XRD analysis?

2) According to the previous reports, high crystallinity of polymer results in high elastic modulus and tensile strength because of brittleness. However, i got an opposite result that amorphous PLA(from XRD) has significantly high elastic modulus (about 2000 MPa) showing high brittleness while crystalline PBAT(from XRD) has significantly low elastic modulus and high elongation properties.

It would be really thankful if you share clear references or solutions!

Thank you in advance!

I‘m going to run a crystal plasticity model with XFEM crack. the material properties are defined as USER MATERIAL. when the job was submitted, an error message was appeared :"39600 Elements are missing elastic property reference. The elements have been identified in element set ErrElemMissingElastic PropRef". I was confused by this message, because the elastic and plastic deformation were descripted in UMAT. but the job can't be submitted sucessfully.

Any response are appreciated, thanks you!

Looking for help regarding the calculation of elastic stiffness constant in N/m unit of a 2D material using energy-strain plot.

Hi,

I am working on numerical simulation of ultrasonic wave propagation through an elastic medium without any defect. I calculated the velocity of wave by using time and distance relationship. But when i used model with void or crack, i got less time to detect the first wave, while it should be longer as there is hole in model and wave propagation through it should be more. Can anyone help me out this problem i.e. how wave velocity is calculated in the model with defect.

Hello everyone,

can anyone provide me the folowing values for Nano-Polycrystalline Diamond (NPD)?

- Young's modulus (elastic modulus (E))

- Heat Capacity

Thanks.

How is possible to calculate Ruess Young's modulus for a composite with three layers? As I know the Ruess young modulus for two layers is calculated from the equation below:

I am perfoming a simulation to determine the elastic/plastic behavior of a polymer material in abaqus.To simulate the plastic behavior of the material I am using a drukcer prager model. I have performed tensile and compression tests in order to determine the input parameters in abaqus (angle of friction, and hardening data). I have encountered convergence problem when I use the linear model, so I am trying to use the hyperbolic model but I do not know how to calculate the parameters for the hyperbolic model (angle of friction, Init Tension), any guideline in how to do it?

Hello everyone,

Recently, I've been trying to conduct a vibration test to obtain the quality factor of a specimen. However, the support boundary inevitably affects the results.

I have tried elastic strips and EPE foams (supporting near the nodal points), but the quality factor varies (~10%) from test to test due to the slight difference in support. The quality factor of the specimen is about 10,000.

I wonder if there are practical treatments to minimize the variation of boundary effect so that the obtained quality factor can be more stable (~1%) during different tests?

Thanks a lot.

Hao

I want to simulate the second harmonic in a nonlinear elastic material, so I choose comsol with murnaghan to describe the third-order elastic constants, but the received waves cannot have second harmonic and the frequency spectrum is the same as the elastic material. I don't know why? the mesh size have been chosed according to double frequency

I am trying to solve a two dimensional elastic problem of following image to find out stress, strain, displacement of the body under the given condition. I intend to use finite difference method for solving the problem

How to reasonably measure the elastic modulus of trees with different trunk heights, especially when the trunk is short and the crown is large?

Note: The tree must be measured intactly, therefore, we cannot cut the crown, we need the elastic modulus of the whole tree.

*****************************************************************************

** UMAT FOR ABAQUS/STANDARD INCORPORATING NON-ELASTIC BEHAVIOUR FOR PLANE **

** STRAIN AND AXI-SYMMETRIC ELEMENTS. **

*****************************************************************************

*****************************************************************************

**

**

**

*USER SUBROUTINE

SUBROUTINE UMAT(STRESS,STATEV,DDSDDE,SSE,SPD,SCD,

1 RPL,DDSDDT,DRPLDE,DRPLDT,

2 STRAN,DSTRAN,TIME,DTIME,TEMP,DTEMP,PREDEF,DPRED,CMNAME,

3 NDI,NSHR,NTENS,NSTATV,PROPS,NPROPS,COORDS,DROT,PNEWDT,

4 CELENT,DFGRD0,DFGRD1,NOEL,NPT,LAYER,KSPT,KSTEP,KINC)

C

INCLUDE 'ABA_PARAM.INC'

C

CHARACTER*80 CMNAME

C

C

DIMENSION STRESS(NTENS),STATEV(NSTATV),

1 DDSDDE(NTENS,NTENS),DDSDDT(NTENS),DRPLDE(NTENS),

2 STRAN(NTENS),DSTRAN(NTENS),TIME(2),PREDEF(1),DPRED(1),

3 PROPS(NPROPS),COORDS(3),DROT(3,3),DFGRD0(3,3),DFGRD1(3,3)

C

C

PARAMETER (M=3,N=3,ID=3,ZERO=0.D0,ONE=1.D0,TWO=2.D0,THREE=3.D0,

+ SIX=6.D0, NINE=9.D0, TOLER=0.D-6, FOUR=4.D0)

C

DIMENSION DSTRESS(4), DDS(4,4)

DOUBLE PRECISION TRVAL, VOID, KAP, PMEAN, SVOLUME, DSVOLUME

C--------------------------------------------------------------------

C

C SPECIFY MATERIAL PROPERTIES

C

C

E = 210000.0

XNUE = 0.3

KAP= 0.01

C

C SET UP ELASTICITY MATRIX

TRVAL = DSTRAN(1)+DSTRAN(2)+DSTRAN(3)

VOID = STATEV (2)

SVOLUME = (VOID+ONE)

PMEAN = (STRESS(1)+STRESS(2)+STRESS(3))/THREE

DSVOLUME = (VOID+ONE) * TRVAL

SVOLUME = SVOLUME - DSVOLUME

EBULK3 = (PMEAN/TRVAL) * (EXP ((SVOLUME/KAP)*TRVAL) - ONE )

EG2 = E/(ONE+XNUE)

EG = EG2/TWO

EG1 = EG/THREE

EG3 = TWO*EG1

EG4 = FOUR*EG1

ELAM = EBULK3

C

C

DO K1 = 1, 3

DO K2 = 1, 3

DDS(K2,K1) = ELAM - EG3

END DO

DDS(K1,K1) = EG4 + ELAM

END DO

C

DDS(4,4) = EG

C

C

C DETERMINE STRESS INCREMENT

C

C

TRVAL = DSTRAN(1)+DSTRAN(2)+DSTRAN(3)

DSTRESS(1) = EG3*(TWO*DSTRAN(1)-DSTRAN(2)-DSTRAN(3)) + ELAM*TRVAL

DSTRESS(2) = EG3*(TWO*DSTRAN(2)-DSTRAN(1)-DSTRAN(3)) + ELAM*TRVAL

DSTRESS(3) = EG3*(TWO*DSTRAN(3)-DSTRAN(2)-DSTRAN(1)) + ELAM*TRVAL

DSTRESS(4) = EG*DSTRAN(4)

C

C UPDATE STRESS

C

DO K = 1,NTENS

STRESS(K) = STRESS(K) + DSTRESS(K)

END DO

C

C

C DETERMINE JACOBIAN

C

C

DO I=1,3

DO J=1,3

DDSDDE(I,J) = DDS(I,J)

END DO

END DO

DDSDDE(4,4) = DDS(4,4)

C

C

RETURN

END

**

I have already written a LS Dyna UMAT code for a linear elastic isotropic material. Now I want to add element deletion to it.

I am simulating fracture using xfem czm for a material (which is ellipsoid in shape) that is inside another material (cuboid in shape).

A prestress is given to the inside material and as intuition says the fracture should initiate where stress concentration happens. And that will be in my case the is the tips of the ellipsoid.

But the maximum principal stress is higher in other regions of the ellipsoid than the tip of the ellipsoid which is not intuitive. Can anyone think of a better reason why this is happening and what can be the best way to initiate a fracture in the material?

*Inclusion inside the host (3D model)*

As you can see the maximum principal stress is not highest at the tips of inclusion but rather highest in other non-concentrated parts of the inclusion.

Please let me know why this is happening and if you know any other better crack initiation criteria other than

**maximum principal stress**in xfem for quasi-brittle material?The geometry of inclusion (the material inside the host):

----------------------------------------------------------------------------------------------

The x:y:z ratios are 4:1:1, so intuitively crack should have formed at the pointy part other than other parts.

This inclusion is indside the host as shown in the attachment and prestress is applied to the inclusion. According to me the maximum principal stress should be highest in the pointy part which is not happening as shown in the results (elastic simulation).

So my question is

1. Why maximum principal stress is not highest in the pointy (stress concentration part)?

2. What are other better criteria for fracture initiation in ABAQUS XFEM for quasi brittle material.

Kindly let me know,.

Regards

Biswabhanu Puhan

What

**failure criteria**can be more efficient for the analysis of**cracked rock mass**under linear**elastic**conditions?The calculation of a model took about 36 hours to solve and I did not select the option to calculate elastic deformations, now I need that parameter and I do not want to calculate everything again.

I am writing a small piece on the definition on long run price elasticities of gasoline/fuel and the length of measurement periods.

I have come across a few studies in the literature reporting unbelievably low elastic modulus for API 5L Grade B steel around 10 GPa while the lowest elastic modulus for this steel in reliable sources is around 180 GPa. Also, the yield strain in their reports is around 3.5% which is huge for elastic deformation in steel. Is this an error in their UTM experiments or something else?

Dear fellow contact mechanicians,

I just stumbled over a problem in analytic mechanics of plane Cattaneo problems in the presence of bulk stress.

It is said that the Ciavarella-Jäger principle for "small enough bulk stress" applies to this problem in the following form:

q(x) = \mu*(p(x; P, beta = 0) - p(x; P - Q/mu, beta)),

where q(x) is the tangential contact traction distribution, p(x) the pressure distribution, P the normal line load, Q the tangential line load, mu the friction coefficient and beta a "rotation angle" proportional to the bulk stress, which I will discuss in a minute.

The second term on the right side in above equation corresponds to a "fictious" normal contact problem of the same contacting bodies under the load (P - Q/mu) and with a relative rotation by beta.

The condition of "small enough bulk stress" is basically that the contact area for this "fictious" problem (which corresponds to the stick region in the actual Cattaneo problem), completely lies within the actual contact area. Moreover, a non-zero value of beta will increase the contact length on one side and decrease it on the other side. So, e.g., for Q = 0 the condition of "moderate bulk stress" is actually that beta = 0, i.e., there is no bulk stress.

Now, we know that tangential contact problems have a loading history. Even the Cattaneo problem has a history: first the normal load is applied, and then an increasing tangential load. However, when beginning to apply the tangential load, Q equals zero, so any (constant) bulk stress will violate the "moderate bulk stress condition".

Or to put it more generally: For any non-zero constant bulk stress, the "moderate bulk stress condition" is violated at the beginning of tangential loading.

Does that change anything about the final contact configuration at the end of the Cattaneo loading?

Or am I missing something?

Thank you very much for your help!

Kind regards,

Emanuel

I am calculating the elastic constants for a crystal with tetragonal symmetry,using VASP . In the INCAR file I have added the following tags :

NSW =1

IBRION =6

ISIF =3

POTIM =0.015

NFREE =4

I am getting 13 components in the elastic tensor instead of 6 . It will be really helpful if anybody can provide any suggestion .

Using the stress strain data obtained from compressive strength test of concrete cylinders how to define the points to estimate the final tangent Modulus of Elasticity and secant Modulus of Elasticity?

Is there any correlation between these two moduli?

To determine the dynamic mechanical properties of PLA compounds it is important to understand their viscous nature (flow properties). Thus, dynamic mechanical analysis (DMA) is performed to evaluate the effect of temperature on the mechanical properties of elegant PLA. Three parameters were used to demonstrate the dynamic mechanical properties of the PLA, i.e. (1) the storage coefficient (E ') corresponding to the elastic response to deformation and related to the material rigidity (2) the loss modulus (E') corresponding to the slag fraction; and (3) the damping factor (tan). These parameters provided qualitative and quantitative information about the thermal behavior of the elegant PLA.

My opinion

The foundation of the wall has a large tread area, in order to distribute the loads on a large ground surface in order to increase the bearing capacity. This really happens when the construction is at rest and all the loads are directed vertically to the ground. When the construction receives lateral loads from the earthquake, the wall along the entire height of the floors, together with its base, tends to overturn. The beams with which it is connected to the nodes react and prevent the overturning of the walls in height. However, the cross sections of the beams are strained with torques and if the torques are large then they fail and we have the collapse of the construction. The weight of the base and the foot girders are not able to stop the overturning in large earthquakes, because the entire height of the walls are huge levers and lower huge torques that the foot girders are unable to receive. It is very important to stop the wall overturning if we want the beams and foot girders not to break We can only do this if we lock the sides of the wall with the ground, as we lock the steering wheel of the car so that it is not stolen from us.

When driving and wanting to turn one hand pushes one side of the steering wheel up and the other down. In the same way it turns the wall in the earthquake and breaks the beams and the foot girders. The vertical force of the side of the wall is received by the base and transmitted to the ground. The upward force of the other side is picked up by the beams and foot girders and they break. If we anchor the sides of the wall with the ground, we will stop the upward force and we will help the beams and the foot girders not to break. It is simple. We remove the base in width, and we make bases in depth, anchored to the ground, so that we receive the vertical forces and the forces that are directed upwards successfully, so that we do not strain the beams and foot girders and break them. The beams also break when the pillar or wall is deformed due to bending. To prevent the bend we use elongated walls with multidimensional cross sections so that they can receive all the horizontal directions of the earthquake.

The walls did not bend easily. If we want to reduce any bending of them, we impose on them by pre-tension compression in the cross section + anchoring in the ground. The pre-tension in the cross section of the wall also increases the elastic displacement, because the cracks that are created are not inelastic but close due to pre-tension and return the wall to its original position. On the other hand they increase the active cross section of the wall due to compression. The shear failure that exists at the concrete and steel interface in the relevance mechanism does not exist since there is no relevance to the prestressing. The foundation soil becomes stronger as the anchorage transfers loads to the lower and stronger compacted soils. The control of coordination and seismic duration is now possible because we control them with external forces coming from the ground.

Dear all,

Can anyone help me to apply an elastic clamping stiffness at a node in Abaqus?

Dear Colleagues

I am using a UMAT for modeling the hysteresis behavior of a Material.

It is a simple UMAT which modify the elastic modulus of the material at different strains in order to reproduce the hysteresis behavior.

I need to convert it into a VUMAT for Explicit Dynamic simulation in ABAQUS.

What should I change in My code?

I have attached my code.

Hi all,

I am working on Phase-Field UEL for hyperelastic materials. I am using codes of Dr Molnar ( http://www.molnar-research.com/tutorials_videos_3.html) to develop hyperelastic material. I have tried to replace the UMAT with my hyperelastic UMAT in the UEL and call the UMAT for stiffness but it's not working and resulting in negative Jacobian.

Any suggestions in implementing hyperelastic UMAT in UEL. Please let me know.

Thanks & Regards,

Sri Harsha

Iam trying to calculate the modulus for my kevlar yarn sample from the results i have obtained using the ASTM D2256, however, Iam not able to find the calculation procedure, can anyone please suggest any literature/material which may contain the details of how to proceed with the calculations.

Thank you in Advance

Hi all,
I'm new to Abaqus and trying to model a 1.4 kg weight laid on the buttocks.
I have an imported buttocks model with element type C3D4H for the hyper elastic materials and C34D for bones.
I assigned boundary conditions of encastre to the bottom part of the buttocks, and the weight can only move in direction toward the buttocks.
I'm using prescribed displacement of the weight and measuring the RF2 on the top nodes of the weight and trying to get ~13.7N (1.4*9.81).
I've assigned surface to surface contact with 0.8 COF between the weight and the area of the buttocks in contact.
I cant seem to get convergence at other part rather then the middle of the buttocks, when the weight is above the peak height...
I tried many things but cant get it to converge, It start to get really slow around 80% and diverge at around 95%, when the loads get to ~12N.
Also the deformation seems a bit large for this small weight.
I would really appreciate some help, I'm attaching the cae file with 3 locations of the weight I tried.
Thank you,
Tomer

Can I know exact assumption for LASSO and Elastic Net? Since Elastic Net is a hybrid method for LASSO and Ridge Regression, did it have the same assumption as them?

Hello Everyone,
I have to simulate the piezoresistive cantilever of poly-silicon. During the selection of material in COMSOL, they ask for an Elasticity matrix. so which value should be entered. I am first time using the piezoresistive cantilever. If anyone knows the answer, kindly please reply.

Thank you

hello how to input materials parameter for the following

elastic - plastic material

I have the following parameters only

lame constants

yield stress

hardening parameter

young modulus and poisson's ratio

I know how to input everything except lame constants

We know that the TERRATEST 5000 BLU is the Light Weight Deflectometer for dynamic plate load test to check compaction quality in earthworks and road constructions.

I am interested in is it possible to assess the strength of asphalt concrete pavements on highways and urban streets using the TERRATEST 5000 BLU (by definition of elastic deflection)?

Currently, I am using MATLAB. I need to look some other tool for solving the Elastic optical network issues.

I am trying to model the impact element having non linear stiffness in Abaqus. I want to model the pounding force between two frames under earthquake excitation. For this I am using Axial connecter element and defined elastic behavior and reference length equal to gap. Under elastic behavior I have input the table of Force vs Relative displacement in such a way that force is zero in tension and remains zero until gap closes. But after running the analysis my pounding force value is comming less than expected.

My whole objective is to model the gap element and it should work in a way that when two frames collide, the gap element becomes active else it should transfer no force?

Please somebody tell me where I am doing wrong or if there is another way of modelling gap in abaqus?

Thanks in advance.

What are the formulae of Voigt, Reuss and Hill Poisson ratio in terms of independent elastic constants (C11, C12, C44) or in terms of bulk and shear moduli for cubic ? Whether they are same or different for all?

PR= (3B-2G) / (6B+2G).

Rocherulle's model and elastic properties

so im modelling a brick wall on ABAQUS, i input elastic and plastic properties for my model and my vertical plastic strain value shows that my model has 0.25. obviously this is so big especially for materials like brick that is a brittle material not elastic, does anyone can help me to solve this problem?thanks in advance

Hi, image there is a case which in the elastic part Young's Modulus depends on the fields, let's say two.

Is it possible to define one field by USDFLD and another by UFIELD? How Abaqus manages this (Start with the USDFLD one or UFIELD one as Field 1)?

How will temperature of submarine sedimentary strata change after it suffers from earthquakes? Will the elastic source give rise to a temperature field?

I was analyzing regression problems with some numerical datasets. Then I saw that the elastic net shows a bad results. But I do not understand why it shows bad results?

I am trying to simulte tensile deformation of Cp Ti. I am using hooke's law for elastic region and phenological power law for plastic deformation. Do we have to use any other model to capture the grain shape changes during tensile deformation?

I am just trying to model a concrete cube with a rubber layer on the top of it...both concrete and rubber layer has linear elastic properties...now when I am giving a pressure load on the top of the rubber, the rubber layer gets spreads to a large extent. How is it happening? I was under the impression that once the rubber gets compressed fully the concrete should come in to picture thereafter and get the pressure.

Hi,

I have given input

**isotropic elastic**properties with*1MPa of young's modulus*,*0.48 Poisson's ratio*,*density 1300*to wall structure (0.5mm thickness).For that, I am getting highest von mises stress after the stenosis region which is about 900Pa (0.0009MPa) and 1385Pa (0.001385Mpa) for systolic(0.4s) and diastolic(0.55s) conditions respectively. I 'ud like to know, how to correlate these results with the given inputs.

Tq in advance,

Regards

There is a soft pneumatic actuator which is made of Hyper Elastic material that I am going to simulate it in Abaqus or Ansys. A

**fiberglass layer**is attached to bottom of actuator. This layer prevents any elongation in both direction (Longitudinal & Transvers ) but allows actuator to bend. How can I simulate it in**Abaqus**or**Ansys**? adding boundary condition or creating property?When the tube array is subjected to water cross flow, what is the effect of fluid flow direction on fluid elastic instability in the tube array? Consider the effect of flow direction, i.e., if the water flow is upward or downward or if the fluid flow direction is horizontal. Many researchers developed an experimental setup in which fluid flows in the horizontal direction; few developed a setup for fluid flow in the vertically upward or downward direction.

Hi,

Can someone please provide me experimental values of the longitudinal or Transversal sound speed for Single Crystal Tantalum and Copper, along with the directions (100), (110), and (111)? I have limited access to journals, and I'm no longer affiliated with a University. There is a paper titled Elasticity of BaFCl single crystal under hydrostatic pressure, which tells elastic constants are related to the speed of sound. It is also well-known people in Geophysics use the speed of sound to find the elastic constants (inverse process) https://www.hindawi.com/journals/mpe/2016/6762076/

Anyways, I need the experimental values of the speed of sound for the crystals mentioned above. I'm trying to publish a final paper of an algorithm for finding the speed of sound for any K direction and a given pressure P . It would be awesome if the results I obtain are close to the experimental data available. I presented part of my work a long time ago at https://meetings.aps.org/Meeting/TSF16/Session/H4.4

Thank you

Oscar Guerrero

Dear all,

I wanted to ask how to resolve the

**error of getting some element negative or zero or small area,**Like with the same mesh with simple elastic or elastoplastic analysis it (abaqus) is not giving the same error .**Only when I am using phase field with subroutine****I am getting this error .****Note:**The specimen I am running the simulation is Compact tension (CT) specimen in 2D .

One of the probable solution I am gonna work on is to ,"Mesh the specimen in Hypermesh" but I do think that it can be done simply in abaqus cause CT specimen is not that complicated specimen to mesh in abaqus with good mesh quality to work with .

Thanks for any future help and also if i find the solution to my problem I will share it in here in the answer to my own question .