Unconvergency with Impact material

[Amirsardar13]

Hi everyone,

I am using an impact material in my model and as far as I understood, it is the only reason of unconvergency after a few seconds for a time history analysis. I am using this combination to do time history analysis. Do you know how I can deal with this unconvergency?
Should I change any of analysis commands such as test, algorithm...? Is there any other material that can substitute for an impact material? Please give me any idea you have. BTW, my model is a bridge and I want to import impact between deck and backwall.
Thank you so much.


wipeAnalysis; # clear previously-define analysis parameters

set T 0;
for {set z 1} {$z<=[expr 30.0/$dt]} {incr z} {


test NormDispIncr 1.0e-4 40 0
algorithm Broyden 8
numberer RCM
constraints Transformation
system SparseGeneral -piv
integrator Newmark 0.50 0.25
analysis VariableTransient # define type of analysis: time-dependent


set ok [analyze 1 [expr $dt] 0.000001 0.02 5]; # actually perform analysis; returns ok=0 if analysis was successful

puts "Time: [getTime]"
}

[fmk]

i suggest you start doing the analysis inside a while loop and try things .. with impact you are oing to have some high frequency stuff you may want to damp out

http://opensees.berkeley.edu/wiki/index ... e_Analysis