L9a | MSE203 Yield criteria and yield surfaces

[@thordan1630]

Old but just want to let you know these videos are still helping people - sincerely a sad engineering student

[@timetheoncelee2961]

even though your body is not transparent, it is excellent that you make me more clear. thanks

[@DONTfakeTOshow]

can you answer this please? "it is known that if the von Mises and Tresca criteria are assumed to agree for the case of uniaxial tension, then they will disagree for the case of pure shear and the von Mises yield circle will circumscribe the Tresca hexagon. SHOW that if it is assumed that the von Mises and Tresca criteria agree for the case of pure shear, then they will disagree for the case of uniaxial tension and the Tresca hexagon will circumscribe the von Mises ellipse)"

[@Conquistadore90]

In 30:21 If i am not mistaken, its supposed to be on the deviatoric plane, not the π-plane.

[@Riegla]

pi plane is correct

[@kamiennagora2073]

Please, remember that von Mises criteria is Huber-von Mises-Hencky criteria. Huber was the first.

[@aeroman777]

But if in the exam question is asked to find the hydrostatic stress after finding the shear stress from von mises, what should be the Ans? And the state of stress we find from von mises is deviatoric? If so, why the trace of the matrix is not zero

[@narayanaswamys7241]

Can you please explain why does a poly crystalline material need five independent slip system for plastic deformation?. How can be proven it using Von Mise criterion?

[@navinnayi2210]

how to calculate dissipated energy in isotropic hardening and kinematic hardening. if i have E = 100 GPa, σy = 100 MPa, κ = 1 GPa is loaded in stain control (1D) with εtot = 0.01. Calculate the plastic strain. What compressive stress is needed to realize one closed hysteresis loop

[@jnarc]

In the first part ,you took sigma y as (sigma1-sigma2)/2 and then while drawing the plain stress graph you took it as (sigma1-sigma2)?? Why?

[@Payitnov]

I don't get why we can conclude that the yield stress for pure sheer is half of that needed for uniaxial tension. WHY?!!

[@DavidDyeIC]

If you do a Mohr's circle for a pure shear t, you get principal stresses of t, -t and 0. Put those into the equation for the Tresca stress, and you find that the min-max principal = 2t. If you do a uniaxial tensile test, you get just the yield stress s_y. So equate these and find that the yield shear stress is equal to t= 0.5 * s_y

[@armankamalzadeh8016]

Imagine we have these Principal stresses: S1=1179.7, S2=411, S3=164.2. According to Mohr circle the maximum shear available in the system is (S1-S3)/2=507.75 While the Von Misus Stress is larger than that Svm=sqrt(0.5((S1-S3)^2+(S1-S2)^2+(S2-S3)^2))=917.3 Would you please elaborate on this?

[@chenjingkai5940]

Because they are different yield criteria.

[@aeroman777]

so the state of stress that we find from von mises criteria is the deviatoric state of stress? how can we find the value of hydrostatic stress value from von mises criteria? will it be always 0?

[@DavidDyeIC]

Because the Von Mises invariant is independent of the hydrostatic stress (try substituting: it's true!), then the Von Mises stress sigma_VM cannot be related to the hydrostatic stress. Physically, since the hydrostatic stress can't cause yielding (a change of shape), then the yielding criterion can't tell you about the hydrostatic stress.

[@fahim0404150]

For the Drucker Prager Hardening Data what laboratory tests should I use for sand and clay? Can you Please Explain? It will be a great Help.

[@aeroman777]

So my exact ques would be "is the trace" of deviatoric stress tensor always 0? If so, why it is not 0 in this case

[@Deepakpatel-xq6dq]

I struggled for about 3hrs how to plot the max stress criteria yield locus.. Thanks so much

[@doublejingforever8161]

I cannot see what you described

[@vshahab3783]

Thanks for sharing the video, certainly useful, however, you may consider giving a better view to the audiences while you are writing on the board .literally, I could not see the board.

[@MrIvanreyes]

Can you recommend a book that teachings linear algebra for civil engineering use?

[@sengtken]

Can you draw von mises signma_1 vs. sigma_2 plane stress envelope with Sigma_3 = Y in uniaxial stress, instead of setting it to 0.

[@michaelabu5772]

Thanks for the video, however I could not really follow because you blocked the board most of the time.

[@nadhirahmopa7464]

if your body is transparent,that'd be better

[@emersonsilva725]

Kkkkkkkk

[@matthewtaylor1892]

Great video, thank you.

[@yousufdinar1244]

You should know we can't see over your body..

[@Ma7m9d]

Are you aware you are being videotaped? maybe to let others understand and follow what you are saying?

[@hassanabdulazim]

Thank you for these helpful videos :)

[@mabusinyambane2609]

Can't see

[@albert0017]

thx for your video~

[@sblingerxu9416]

Guest-Tresca

[@arash4232]

I am so sorry to say that this video is not prepared in its best form.