Questions tagged [stiffness]
43 questions
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How does width and thickness affect the stiffness of steel plate?
I have a 2 mm thick steel plate which is 300 mm long and 30 mm wide, supported at either end. It supports a weight-bearing wheel that can roll along the plate. It currently supports the maximum weight that I expect it to support when the wheel is in…
jhabbott
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Why does a jumping rope have no bending stiffness and compression stiffness?
Can anyone just tell me that why doesn't a jumping rope, or any other kind of rope, have any bending stiffness? If I hold one end of the rope in my hand, the rest of the rope will just fall. It won't just keep itself straight. I know it is because…
Rameez Ul Haq
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Elasticity of a drilled plate
If I take a large thin plate and I uniformly drill a very large number of holes (diameter "d") very close together (minimum spacing "s"), what will be the stiffness of this new plate? When I say "stiffness" I mean the derivative of average…
Nic
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What are the elastic constants for tetragonal zirconia polycrystal (TZP)?
I have six known elastic constants of TZP. What is the relationship between the known and the unknown constants?
Known constants (GPa):
$c_{11}=327\\ c_{12}=100\\ c_{13}=62\\ c_{33}=264\\ c_{44}=59\\ c_{66}=64$
How can I find the others? Is…
Jimmy
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How much does the elasticity (Young's Modulus) of concrete and asphalt change with ambient temperature?
I'm assuming here that all materials will have a change in elasticity due to thermal expansion/contraction and a resultant reduction/increase in the strength of the bonds of the atoms leading to a varying young's modulus. But how significant is it…
Noobie
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FEM - is symmetry a boundary condition?
In FEM is symmetry technically a boundary condition?
For example using the FEM on a symmetrically loaded and supported beam. The FEM can be simplified by using symmetry.
However, is this symmetry just implemented as a boundary condition or is it…
FEA42
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Degrees of freedom of an internal hinge in plane beam?
What are the degrees of freedom of an internal hinge in a plane beam?
I understand that the bending moment=0, does this mean there is no slope either?
Or does it have both degrees of freedom of deflection (V) and slope (θ)?
FEA42
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4
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2 answers
Dominant parameters in the dynamical response of a linear oscillator
I am working with a very simple 3-DOF damped LTI spring-mass system. As an exercise I am altering two parameters simultaneously (stiffness and damping coefficients connecting mass 1 to mass 2) to see which combination minimizes:
Settling…
willpower2727
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How does stiffness/rigidity affect the bending moment of a beam
My question may sound silly as it’s mainly good sense but I may be mixing things up.
Let’s consider a flexible cantilever beam of a given length and material is fixed at one end and free at the other end.
Let’s suppose a dead weight is put at the…
R. Brown
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How quadrilateral elements represented in most FEA solvers for structural mechanics problems?
How quadrilateral elements represented in most FEA solvers for structural mechanics problems?
I know that Nastran-95 represent quadrilaterals for membrane and bending elements as a set of triangles:
At the same time there are a lot of literature…
Евгений Павлов
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3
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How do FE solvers solve the case of panel buckling under pure shear?
How do FE solvers solve the case of panel buckling under pure shear?
The main problem is that global matrix of initial stess is singular in that case. One method is to apply some forces that shear is not so pure. But I think there should be some…
Евгений Павлов
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What is the deflection of planet-ring Gear Mesh along the pressure line and the position of the Plant gear?
For a Sun-Planet mesh in a planetary gear train, there will be a deflection $\delta_{sn}=\delta_{s}-\delta_{n}$ along the pressure line and the position of the planet will be determined by $\psi_{n}$, and by looking at the geometry of the picture…
spe4ker
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Definition of stiffness for structural dynamics: How would you find the stiffness of an unusual beam directly?
I have a structure which is essentially a curved beam (not an arch or anything simple) which I have modeled in microstran/spacegass. It looks something like this:
Or for something more simple, imagine I have a beam like this:
The definition of…
Noobie
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2
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Transforming the Area of a Hollow Square Section filled with concrete into the equivalent area of just steel
I need to complete the 3D stiffness matrix of steel concrete composite columns under all kinds of stresses (axial and rotational as shown in the image below). So because the section is a Square Hollow Section 150 x 150 x 16mm, filled with concrete,…
CADCivilEngStudent
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Brittle = highly stiff but not very strong
I was trying to imagine materials undergoing collisions, and thought about materials that do not deform at all. Naturally this is an idealization that does not exist in reality but, if it did, I think it would be a material with infinite…
user442920
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