Automatic Spring Elements Created

SOFiSTiK Teddy
1

I am modelling HEB200 beam of length 4.8mm using Teddy. The code will be pasted below. The code works well without any error. I first created 2d cross section using points (spt) and then connected the points with lines (sln) and grouped it into a area using sar fields. Finally extrude it for 4.8m

My question:

  1. Why does sofistik create spring elements at the cross section created?
  2. Why is a way to extrude HEB cross section created using “Prop” syntax and mesh the structure with Bric Volumn element?

The code is as follows:

+PROG AQUA URS:2
head material definition
norm din 1045-1
CONC NO 2 TYPE C FCN “30” TITL “C 30/37 (EN 1992)”
$STEE NO 2 TYPE B CLAS “500B” TITL “B 500B (EN 1992)”
$prof
end

+prog sofimshc urs:1
head Sectional quad mesh
syst 3D gdir negz gdiv 100000
ctrl mesh 0.5
ctrl hmin 0.05[m]
ctrl DELN 0 $ no deletion of auxiliary structural line
echo full val extr
ctrl

$ structural points — now in YZ plane (X=0)
spt 1 0 -0.1 -0.1
spt 2 0 0.1 -0.1
spt 3 0 0.1 -0.085
spt 4 0 0.0045 -0.085
spt 5 0 0.0045 0.085
spt 6 0 0.1 0.085
spt 7 0 0.1 0.1
spt 8 0 -0.1 0.1
spt 9 0 -0.1 0.085
spt 10 0 -0.0045 0.085
spt 11 0 -0.0045 -0.085
spt 12 0 -0.1 -0.085

$ structural lines
sln 1 npa 1 2
sln 2 npa 2 3
sln 3 npa 3 4
sln 4 npa 4 5
sln 5 npa 5 6
sln 6 npa 6 7
sln 7 npa 7 8
sln 8 npa 8 9
sln 9 npa 9 10
sln 10 npa 10 11
sln 11 npa 11 12
sln 12 npa 12 1

!*!Label Area defination with lines
sar 10 grp 1 mno 2 t 0 nra 0 mctl 1
sarb out nl (1 12 1) mno 2

!*!Label Path for extrusion
sln 101
slnb x1 0 y1 -0.1 z1 -0.1 x2 4.8 y2 -0.1 z2 -0.1

!*!Label Point support
spt 201 x 0.0 y 0.0 z -0.1 fix PPMM
spt 202 x 4.8 y 0.0 z -0.1 fix PPMM

!*!Label 1st structural line
spt 301 x 1.4 y 0.1 z -0.1
spt 302 x 1.4 y -0.1 z -0.1
SLN 303 NPA 301 NPE 302 fix XP GRP 1

!*!Label 2nd Structural line
spt 401 x 3.4 y 0.1 z -0.1
spt 402 x 3.4 y -0.1 z -0.1
SLN 403 NPA 401 NPE 402 fix XP GRP 1

!*!Label Line load
sln 102
slnb x1 0 y1 0 z1 0.1 x2 4.8 y2 0 z2 0.1

end

+prog sofimsha urs:3
head Extrusion to volume
syst REST
$extr QUAD from SAR 10 path SLN 101
grp 2
bric prop mno 2
extr type quad grp 1 path sln 101

end

+prog sofiload urs:4
head Loads Defination
act G $ permanent action
act Q $ varaible action

!*!Label Self-weight
$LC 1 type G dlz 1 titl “Self Weight”
LC 1 type G facd 1 titl “Self Weight”

!*!Label varaible load: Line load
$LC 2 type Q titl “Line Loads without deadweight”
$ line sln 102 type PG P1 70 P2 10 x1 0.0 y1 0.0 z1 0.1 x2 2.4 y2 0.0 z2 0.1
LC 2 type Q facd 1 titl “Line Loads”
line sln 102 type PG P1 1000 P2 1200 x1 2.4 y1 0.0 z1 0.1 x2 4.8 y2 0.0 z2 0.1

!*!Label Varaible load: Point load

LC 3 type Q titl “Point load”
poin ref sln no 102 type PZZ P -550 x 2.4 y 0.0 z 0.1

$LC 5 type Q facd 1 titl “Point load with deadload effect”
$ poin ref sln 102 type PZZ P -2.5 x 2.4 y 0.0 z 0.1

end

+prog ase urs:21
head Linear analysis
echo full extr
lc alle
end

Please let me know if anything is unclear.
Thank you in advance.

2

The spring elements originate from the command
SARB OUT NL (1 12 1) MNO 2.

With MNO 2, you define a material as a boundary, which is then interpreted as spring elements with the stiffness properties of material 2.

Question 2 I dont understand

3

Thank you very much for your help. I removed the material part from SARB, Sofistik does not create spring elements anymore.

Regarding second question.

I have created HEB beam by converting points into line and then lines to area. Used this area to extrude along the lengths to create to create a solid 4.8m long Beam.

Problem with this method is its too long procedure and i could not create a radius between the intersection of web and flange ( Hence,i have sharp corners… which results in stress singularity).

I want to use built-in PROF field
prof 44 HEB 200 dtyp S
With this field, i could only create Beam elements and i want to have solid bric elements. Is it possible to create a extrusion for 4.8m with Solid Bric element with PROF syntax.

I am completely new to Sofistik and Teddy. I have also not worked with Sofiplus-X (because we do not have Sofiplus-X license)

4

why do you want volume elements instead of beam elements?

5

I need accurate stress and strain data to calibrate FEM model with sensors data and volume elements would be a better choice. Although beam elements would give good global response like moments and forces, i am more interested in local effect