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Solved LSDYNA problem

resonance (natural) frequency of a cantilever beam is given by

f=[k_n/2pi][sqrt(EI/wL^4)] where, k_n=3.52 for mode 1, E is Young's modulus, I is moment of Inertia, w is beam width, L is beam length. (this is from Formulas for Stress and Strain, 5th edition by Raymond J. Roark and Warren C. Young).

 I would like to derive this formula. Can any one suugest me any book or any link?  

I am trying to implement quasi static fracture in a discrete lattice model, with material being viscoelastic. Do i need to use an incremental-iterative method? Please give your suggestions.

I have a question making me no sleep. In the elastic theory we have a separable Lagrangian L = T(v) + W(u) since we can write the internal elastic energy as a function of displacements. What happens if we use a rate form for the strain and the stress? Can we write the potential energy in terms of just velocities? If that is the case the stationary path of the Lagrangian reduces to:

 d/dt (dT/dv - dW/dv)  = 0

Hi,

I am using a X-FEM Matlab code found here http://people.civil.gla.ac.uk/~bordas/xfemMatlab.html"]http://people.civil.gla.ac.uk/~bordas/xfemMatlab.html

In branch.m/branch_node.m (both functions of radius r and angle theta) crack tip fields are defined...and questions arise.

% Functions



f(1) = r2 * st2 ;

f(2) = r2 * ct2;

f(3) = r2 * st2 * ct;

f(4) = r2 * ct2 * ct;

can anybody provide me softcopy of the book or any online material of AMPL modeling language book.

Dear Members I am working in the area of Fracture Mechanics and natural element method.Currently i am trying to calculate Stress Intensity factor of cracked Homogeneous plate.I wanted to use Interaction Integral Method to seperate Complex stress intensity factor.I need auxiliary state formulas for Homogeneous materials.Please if it is possible send me an article with formulas.

Hello,

Most of us use LaTeX + BibTeX for writing papers and research reports. Personally, I use MS Word for other document types but not for research papers and reports---even if I mostly use Windows. In case it matters: I use MikTeX v. 2.4 as the main TeX technology platform; TeXnicCenter v. 1 Beta 6.21 or Texmaker v. 1.5 for editing; and JabRef v. 2.2 for the management of the BibTeX database, all on Win2K Pro.

Hi everyone ,

I am a Graduate student and working on mesh free techniques.

I want to know more information regarding Mesh free technique using moving least square method which can replace the finite element method.

Thank you