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can the TLFD8nBrick element be used in the transient analysis？
I have tried to simulate a model using TLFD8nBrick elements, But it seems that it can't be used in in the transient analysis？ there are so many bugs，it also can't apply its selfweight by using brickW command？
so who can help me ? thanks !

any one help me ?

dear all , i want to simulate the freely falling body of a cube by using the stdbrick element, the bodyforce is needed, but it seems that the results don't conform to the newton second law，do I need to define the acceleration ？ please help !thanks !

dear fmk
it seems that I found a bug about noderange command.
I want to record 4,879 nodes' displacements ,But I only got 4,509.\
while I use nodeall command in 2.1.0 , It's OK.

[quote="fmk"]you can't .. that what happens when you remove an element, the resisting forces that it supplied are gone, the nodes are unbalanced and equi must be restored on the next step.[/quote]



deer fmk
I have a question about elements death（remove elements command）
as I know, other FEM softwares as ansys , abaqus and so on ，they kill elements by multiplya minimal coefficient to the stiffness matrix.what about opensees? does it delete the elements directly from the model? if it is ,how can I change the remove elements methods ？

thanks vesna. I also think so .
thanks fmk , I make sure I have remove the invalid nodes because I have written some tcl commands to judge wether it is necessary to kill the nodes by using getEleTags and getNodeTags Commands . I have test a solid beam by killing elements during analyzing.it runs well .
so I want to know how I can fix the problems when I kill too many elements ？ another question ， it seems that the died elements release their stresses to the next step disposable， that makes the residual elements increase their stresses suddenly，so many elements reach the stress level. how can I fix it ?

dear all :
I use "remove" command to kill the solid elements by testing the Mise stresses .
while I have met a difficult problem： if I kill too many elements during the analyze , it will throw an error “ 0x7c931948 0x00000000 read （I don't know how to translate it to English） or !!!pfsfct(): The diagonal entry 46812 is zero !!!
In SymSparseLinSolver: error in factorization.
WARNING Linear::solveCurrentStep() -the LinearSOE failed in solve()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 0.75
OpenSees > analyze failed, returned: -3 error flag”
and cann't complete the analyzing successfully . can you tell me why？ about the stiffness matrix？thanks！

I want to compare these two lists ,if they have the same tags , pick up the tag , it can run successfully if I don't use “for” loop .but now it failed ,why ?
help

set tags1 {77 78 81 80 86 87 90 89
82 83 86 85 91 92 95 94
83 84 87 86 92 93 96 95
85 86 89 88 94 95 98 97
86 87 90 89 95 96 99 98 }


set tags2 {77 78 81 80 86 87 90 89
82 }


set unkillednum [llength $tags2 ]

for {set i 0} {$i < $unkillednum } {incr i} {

set q [lindex $tags2 $i ]
puts $q

lsearch $tags1 $q

}

need help ，please

several questions about Tcl

dear all ， here I have several questions about Tcl

1 ： I have gotten a line including some node tags ， have can I set each strings to

node tags ？

for example

set fd [open "3.tcl" r]
:
:
:
set Value [string range $line [expr $equalpos + 1] [expr $commentpos -1]]
puts $Value

now I get :
* 1 25 360 2123 20120 ....
how can I set the" 1, 25, 360,2123, 20120 ... " these numbers to the node tags ?

2 : how can I add "#" to an assigned position ？for example the head of a line in a tcl by using tcl command ？

for example :

element 1 2 3 4 5 6 7 8 5 .....

to---------

# element 1 2 3 4 5 6 7 8 5 .....

thanks！

me too .any one can help me .

my email is liushuhao2004@yahoo.com.cn .thanks

me too .any one can help me .

my email is liushuhao2004@yahoo.com.cn .thanks

dear fmk
can you tell me how can I get the Gausspoints of the stdBrick element ？
annother question， I have found that the Gausspoints of the Brick8N element are different from othe FEA software ， I want to get the stresss of the nodes from the Gausspoints , I want to know the relationship between the GPTS and nodes in the stdBrick / Brick8N element ,thanks

thanks fmk
while i found it seems that the OS can calculate more elements when I use stdBrick than Brick8N .why ?
another question, how can I get the Gusspoint coordinates of the stdBrick ?
I really want to use stdBrick elements , did you release the 2.2.1 version ?