Recovery Flag

  1. Natahn Scott Hosking

    I have a few questions about the use of the recovery flag in VABS (either linear or non-linear beam theory).  

    Turning the flag on or off is no problem.  The next step is to define the required recovery input.  In a simple linear beam theory case with the recovery flag set to '2' and all other tags set to '0' you are required to enter the following data:

    u1 u2 u3

    9 elements of the cosine matrix

    F1 M1 M2 M3


    When I run the example input found in the VABS manual:

    0 0 0
    1 0 0
    0 1 0
    0 0 1
    1 0 1 0

    I will get an error in the read of the file and an error occurs in my 'ECH' file.  I have found that in order to get this to run I need to input (extra zeros in the first and 4th lines):

    0 0 0 0
    1 0 0
    0 1 0
    0 0 1
    1 0 1 0 0


    Can someone explain why this is happening?

    My next question involves the output files.  If anyone can clarify how the output data is displayed.  The manual does an excellent job explaining the 'ELE' file but I find myself having questions about the other files and clarity would be nice.


    Thanks in advance to anyone who can help me with these questions.  It is greatly appreciated!


  2. Ning Liu

    Hi Natahn,

    I suggest you open your ECH file and read the part where you put zeros, see what are these extra zeros' function. ECH file says very clear about the function of your each input data, e.g. displacement, stress resultants.

    .U stores displacements, .SN stores nodal stresses


  3. Natahn Scott Hosking


    If I don't put the extra zeros in it reads everything improperly.  It added the zeros to make sure the ech file displayed the proper data input.


    I also understand what each file extension means (as explained in the manual) but I was just looking for clarification on what each column and row meant.


    Thanks for helping!