Recent content by dilberg

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    Understanding Residual Stresses: Books & References

    I am interested in effect of residual stresses on fatigue cracks. I have a parametric model of a fracture specimen, and I am trying to model residual stress pattern (due to prior yielding, probably due to fluctuating loads) as a predefined field as PerrenaII mentioned. From literature I gather...
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    Understanding Residual Stresses: Books & References

    I'm having some trouble understanding residual stresses. I need to model a residual stress pattern into a finite element model. Can someone recommend books or references that has computations with residual stresses?
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    Calculating Stress/Deflection in Cantilever Beam

    Rectangular cross-section. The crossection will only affect I, in the formula. We can just keep it as I, so we don't have to worry about the cross-section.
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    Calculating Stress/Deflection in Cantilever Beam

    In this formula V is the vertical shear on a cross section. Applied shear (T) is horizontal on the upper surface. Why should they be equal?
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    Calculating Stress/Deflection in Cantilever Beam

    A cantilever beam is loaded by a uniform shear stress T on its upper surface. How to calculate the stress and deflections at the end of the beam?
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    How Long Does It Take a Rolling Sphere to Reach the Edge of a Rotating Platform?

    The radius of the platform is b. The sphere is released at r=ro at t=0. The problem says it rolls without slipping, but say if it were to slip after some time t then alpha=a/R is no longer valid. Any thoughts on how to approach this condition? I have a question about inertia tensor. How to...
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    Summing series using contour integrals

    I would be grateful if someone can help me take this sum. Evaluate the following sum 1/(n^2-4)^2, the sum goes over all positive integers n= 1,3,4,5...infty except 2. If it weren't squared I think I can figure it out( I remember my professor telling something about mutliplying by a...
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    How Long Does It Take a Rolling Sphere to Reach the Edge of a Rotating Platform?

    My analysis is as follows, For a reference frame attached to the center of the sphere, a cenrtifulgal force mrw^2 acts radially outwards. Newton's law implies, mrw^2-mg*mu=ma Take torque about the center of the sphere, mumg*R=I*alpha alpha=a/R eliminating mumg, I get...
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    How Long Does It Take a Rolling Sphere to Reach the Edge of a Rotating Platform?

    A circular platform of radius b has a radial groove and is rotating with a speed w about central axis. A sphere of radius R and mass M rolls in the groove without slip. There is friction at the bottom. I need to calculate the time required for the ball to reach the edge. Any ideas on how to do...
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