Difference between revisions of "Contrib:KeesWouters/shell/static"

Revision as of 12:58, 7 March 2010

Static analysis of a shell construction

[ .... under construction .... ]

This contribution is in close cooperation with Bridge.

In this example the following items are discussed:

• preproccesing:
• definition of geometry in Salome
• partitioning of the geometry and groups
• meshing of the geometry
• definition of the groups
• (maybe: python script which makes editing much easier ...)

• static analysis with pressure or force applied on a group or nodes

• postprocessing:
• viewing displacement in Salome
• determination of stresses

• interface ASTK

Definition of the geometry

planar shell Geometry:

• L = 11.38 m
  
• Thickness = 0.55 m
  

Loads:
[type] [group] [value]

• Presure1 (Fbot) = 29.5e3 Pa
  
• Presure2 (Fmain)= 25.8e3 Pa
  
• Presure3 (Ftop) = 24.3e3 Pa
  
• Presure4 (Fcentre1,Fcentre2)= 182.6e3 Pa
  

Boundary conditions:

• Lbot (DX=0.0, DY=0.0, DZ=0.0)
  
• Ltop (DZ=0.0)
  

Material:
Concrete

• E = 32e9 Pa
  
• Nu = 0.2
  

Create all points and lines using: [New Entity]->[Basic}->[Point] and [New Entity]->[Basic]->[Line]

Create one big face Ftotal [New Entity]->[Build]->[Face]
Ftotal: Line7,Line6,Line8,Line12,Line11,Line10,Line9,Line1

Create three wires [New Entity]->[Build]->[Wire]

• Wire1: Line3,Line4,Line5
  
• Wire2: Line17,Line18,Line19
  
• Wire3: Line13,Line14,Line15,Line16
  

Create vector [New Entity]->[Basic]->[Vector]
(0,0,1)
Create four extrusions [New Entity]->[Generation]->[Extrusion]

• Extrusion1: Wire1,vz
  
• Extrusion2: Wire2,vz
  
• Extrusion3: Wire3,vz
  
• Extrusion4: Line2,vz
  

Partitioning of the geometry

why: we need groups for loads and boundary conditions
how: we define planes

Create partition [Operations]->[Partition]

• Part_main: Ftotal,Extrusion1,Extrusion2,Extrusion3,Extrusion4
  

Meshing

how
tria -quad?
linear vs quadratic elements

ASTK - Aster

Postprocessing

displacements

local stresses

equivalent stresses