Skip to content

2D Elements

MIDAS PYTHON

PLATE

A nested class within Element used to create Plate elements.

Object Attributes

ID: Element ID
TYPE: Element type = 'PLATE'
MATL: Material ID of the plate element
SECT: Section/Thickness ID of the plate element
NODE: Nodes of element in list. eg: [1,2,3,4]
ANGLE: Beta angle of the plate element
AREA : Area of Plate element
NORMAL : Normal vector of the Plate element eg: (0,0,1)
CENTER : Centroid location of the Plate element (x,y,z)
STYPE: Type of Plate element
    1 : Thick   |   2 : Thin   |   3 : Thick w Drilling dof   |   4 : Thin w Drilling dof

To create Plate element we have total 2 methods :

1. Plate

Element.Plate(nodes:list, stype:int=1, mat = 1, sect = 1, angle = 0, group = '' , id=None)
Creates a Plate element.

Parameters

  • node: Nodes of the Plate element
  • stype (default=3): Sub Type of Plate element
         1 : Thick   |   2 : Thin   |   3 : Thick w Drilling dof   |   4 : Thin w Drilling dof
  • mat (default=1): Material ID of the Plate element
  • sect (default=1): Thickness ID of the Plate element
  • angle (default=0): Beta angle of the Plate element
  • group (default=''): Structure group of the element and its nodes(can be str or list eg. 'SG' or ['SG1','SG2'])
  • id (default=None): Manually assign an ID. If None, ID will be auto-assigned.

Examples

Node(0,0,0)
Node(1,0,0)
Node(1,1,0)
Node(0,1,0)
Element.Plate([1,2,3,4])

Node.create()
Element.create()

2. Plate.loftGroups

Element.Plate.loftGroups(strGroups:list, stype:int=1, mat = 1, sect = 1, angle = 0, group = '' , id=None , nDiv:int=1 , bClose:bool=False)
Creates Plate elements connecting the nodes in Structure groups.

MIDAS PYTHON

Parameters

  • loftGroups: List of Structure groups whose nodes are to be used(eg. ['SG1','SG2','SG3']) .
         Min. 2 groups with 2 nodes are nodes are required.
  • stype (default=3): Sub Type of Plate element
         1 : Thick   |   2 : Thin   |   3 : Thick w Drilling dof   |   4 : Thin w Drilling dof
  • mat (default=1): Material ID of the Plate element
  • sect (default=1): Thickness ID of the Plate element
  • angle (default=0): Beta angle of the Plate element
  • group (default=''): Structure group of the element and its nodes(can be str or list eg. 'SG' or ['SG1','SG2'])
  • id (default=None): Manually assign an ID. If None, ID will be auto-assigned.
  • nDiv (default = 1): Number of divisions between each loft.
  • bClose (default=False): Whether to close the loop or not.

Examples

Element.Beam.SDL([0,0,0],[1,0,0],10,10,group='SG1')
Element.Beam.SDL([0,1,0],[1,0,0],10,10,group='SG2')
Element.Beam.SDL([0,3,0],[1,0,0],10,10,group='SG3')

Element.Plate.loftGroups(['SG1','SG2','SG3'])

Node.create()
Element.create()

3. Plate.fromPoints

Element.Plate.fromPoints(points: list, meshSize=1.0 , meshType='Tri', innerPoints=None , stype = 1, mat = 1, sect = 1, angle = 0, group = "" , id = None )
Creates meshed Plate elements connecting the boundary points.

MIDAS PYTHON

Parameters

  • points: List of points representing outer boundary(eg. [(x1,y1,z1) , (x2,y2,z2), (x3,y3,z3)]) .
  • meshSize: Mesh size .
  • meshType: Type of meshing (Tri or Quad).
    Gmsh is being used for meshing. So, depending upon points and innerPoints input , Quad mesh-size can differ or Quad meshing can even fail.
  • innerPoints (optional): List of points representing internal holes can be single or multiple holes.
        Single hole - [(x1,y1,z1) , (x2,y2,z2), (x3,y3,z3)]
        Multiple hole - [[(x11,y11,z11) , (x12,y12,z12), (x13,y13,z13)],[(x21,y21,z21) , (x22,y22,z22), (x23,y23,z23)]]
  • stype (default=3): Sub Type of Plate element
         1 : Thick   |   2 : Thin   |   3 : Thick w Drilling dof   |   4 : Thin w Drilling dof
  • mat (default=1): Material ID of the Plate element
  • sect (default=1): Thickness ID of the Plate element
  • angle (default=0): Beta angle of the Plate element
  • group (default=''): Structure group of the element and its nodes(can be str or list eg. 'SG' or ['SG1','SG2'])
  • id (default=None): Manually assign an ID. If None, ID will be auto-assigned.

Examples

# PLATE MESHING WITH SINGLE HOLE

from midas_civil import *
import math

# Creates circle with given radius and center
def CirclePts(origin,radius,nSides):
    pts = []
    for i in range(nSides):
        theta = i*2*math.pi/nSides
        pts.append([origin[0]+radius*math.sin(theta),origin[1]+radius*math.cos(theta),origin[2]])
    return pts

innerHole=CirclePts((0,0,0),6,16)
outerBoundary = [(-10,-10,0),(10,-10,0),(10,10,0),(-10,10,0)]

Element.Plate.fromPoints(outerBoundary,1,'Tri',innerPoints=innerHole,sect=2,group='Pile Cap')

Node.create()
Element.create()

# PLATE MESHING WITH MULTIPLE HOLES
from midas_civil import *
import math

# Creates circles with given radius and center
def CirclePts(origin,radius,nSides):
    pts = []
    for i in range(nSides):
        theta = i*2*math.pi/nSides
        pts.append([origin[0]+radius*math.sin(theta),origin[1]+radius*math.cos(theta),origin[2]])
    return pts

innerHole=[CirclePts((-5,-5,0),3,16),CirclePts((-5,5,0),3,16),CirclePts((5,-5,0),3,16),CirclePts((5,5,0),3,16)]
outerBoundary = [(-10,-10,0),(10,-10,0),(10,10,0),(-10,10,0)]

Element.Plate.fromPoints(outerBoundary,2,'Tri',innerPoints=innerHole,sect=2,group='Pile Cap')

Node.create()
Element.create()

4. Plate.extrude

Element.Plate.extrude(points: list , dir:list , nDiv:int=1 , bClose:bool=False , inpType='XYZ' , stype = 1, mat = 1, sect = 1, angle = 0, group = "" , id = None)
Creates meshed Plate elements connecting the boundary points.

MIDAS PYTHON

Parameters

  • points: List of points to be connected and extruded. Input depends upon the inpType.
  • dir: Direction and length of extrusion (eg. (0,0,2) - extrude along z direction by 2 units)
  • nDiv: No. of divisions along the extrusion.
  • bClose: Whether to close the loop or not.

  • inpType: Type of points input (eg. XYZ or ID or NODE)
         1 : XYZ - points (list(x,y,z)) = [(x1,y1,z1) , (x2,y2,z2), (x3,y3,z3)]
         2 : ID - points (list(int)) = [nID_1 , nID_2 , nID_3]
         3 : NODE - points (list(Node)) = [Node1 , Node2 , Node3]

  • stype (default=3): Sub Type of Plate element
         1 : Thick   |   2 : Thin   |   3 : Thick w Drilling dof   |   4 : Thin w Drilling dof

  • mat (default=1): Material ID of the Plate element
  • sect (default=1): Thickness ID of the Plate element
  • angle (default=0): Beta angle of the Plate element
  • group (default=''): Structure group of the element and its nodes(can be str or list eg. 'SG' or ['SG1','SG2'])
  • id (default=None): Manually assign an ID. If None, ID will be auto-assigned.

Examples

from midas_civil import *
import math

def CirclePts(origin,radius,nSides):
    pts = []
    for i in range(nSides):
        theta = i*2*math.pi/nSides
        pts.append([origin[0],origin[1]+radius*math.sin(theta),origin[2]+radius*math.cos(theta)])
    return pts

Element.Plate.extrude(CirclePts((0,0,0),6,5),(10,0,0),4,True,inpType='XYZ')

Node.create()
Element.create()

Examples

1. Silo

import math
R_top=5.0   # Radius at the top of Silo
R_bot = 2.5 # Radius at the bottom of Silo < R_top

H_tot=20.0 # Total height of Silo
H_tap = 5  # Height of tapered portion < H_tot

nR=32      # Sides of cylinder
nH=20      # Divisions along height

for q in range(nH+1):
    for i in range(nR):
        theta = i*2*math.pi/nR
        R = min(R_top,R_bot+q*H_tot/nH*(R_top-R_bot)/(H_tap))
        Node(R*math.sin(theta),R*math.cos(theta),q*H_tot/nH)

for q in range(nH):
    n_list = list(range(q*nR+1,(q+1)*nR+1))
    for i in range(nR):
        n1=n_list[i]
        n2=n_list[(i+1)%nR]
        Element.Plate([n1,n2,n2+nR,n1+nR])

Node.create()
Element.create()
NODE GRID

WALL

A nested class within Element used to create Wall elements. (Only applicable in GEN NX)

Wall

Element.Wall(nodes: list, stype: int, wtype:int , wID:int , mat , sect , group = "" , id: int = None)
Creates a Wall element.

Parameters

  • node: Nodes of the v element

  • stype (default=2): Sub Type of Wall element
         1 : Membrane   |   2 : Plate

  • wtype (default=2): Wall type
         0 : Plate Base   |   1 : CRB-Pin   |   2 : CRB-Fixed

  • wID (default=1): Wall ID of the Wall element

  • mat (default=1): Material ID of the Wall element
  • sect (default=1): Thickness ID of the Wall element
  • angle (default=0): Beta angle of the Wall element
  • group (default=''): Structure group of the element and its nodes(can be str or list eg. 'SG' or ['SG1','SG2'])
  • id (default=None): Manually assign an ID. If None, ID will be auto-assigned.

Object Attributes

ID: Element ID
TYPE: Element type = 'WALL'
MATL: Material ID of the Wall element
SECT: Section/Thickness ID of the Wall element
NODE: Nodes of element in list. eg: [1,2,3,4]
ANGLE: Beta angle of the Wall element
AREA : Area of Wall element
NORMAL : Normal vector of the Wall element eg: (0,0,1)
CENTER : Centroid location of the Wall element (x,y,z)
STYPE: Sub-Type of Wall element
     1 : Membrane   |   2 : Plate

WTYPE: Wall type
     0 : Plate Base   |   1 : CRB-Pin   |   2 : CRB-Fixed

WID: Wall ID of the Wall element

Examples

Node(0,0,0)
Node(1,0,0)
Node(1,1,0)
Node(0,1,0)
Element.Wall([1,2,3,4])

Node.create()
Element.create()