education

Hello,

It would be grateful if someone could explain me how to calibrate arc length increment factors in Static, Riks method in Abaqus.

For a default input in Static, Riks step I get max LPF factor equal 147(this value is probably correct, expected 147.8). Unfortunately, I'm not satisfied in number of increments(the result of 12 increments). The question is: how to calibrate arc length increment factors(initial, minimum, maxium arc length increment and estimated total arc length) to get more accurate results.

I found something about it, quote:

Hi 

  I have MDOF equation:

                MX"+CX'+KX = F(t).

 Say the order of each matrix is  nXn. I want to reduce the order of the matrices. 

I will find the eigen vectors and get modal vectors matrix phi. I will pick some dominating frequencies say around 24 modes.

then reducedM = phi'*M*phi.

I am student and learning beam theory. I am trying to solve Euler-Bernoulli 4th order differential equation to find the deflection of a beam.  The equation is

EI v''''(x) = w

where v is the transverse deflection and w is the distributed uniform load on the beam. 

But how would you solve the above if the beam is fixed on both ends, and instead of w, I have a point load P at say distance 'a' from the left end?  For a beam fixed on both ends, I use the following boundary conditions