Civil Engineering Reference
In-Depth Information
A widely used three-dimensional element, the 20-node hexahedron, is the subject of
the example that goes with this program. The element is the three-dimensional analogue
of the 8-noded quadrilateral in plane problems with the element node numbering indicated
in Figure 5.23.
The example and data of Figure 5.24 are for a simple boundary value problem where
an elastic block carries a unit uniform load over part of its top surface. The block has
58
0.5m
59
UDL of 1.0
applied to top
of element 1
L
52
60
39
z
33
40
53
20
41
21
62
14
34
y
5
22
1
E=100kN/m
2
u
=0.3
43
15
65
2
3
24
3
x
55
4
1
46
67
5
36
2m
6
27
6
48
8
E=50kN/m
2
u
=0.3
17
70
7
29
4
57
9
2
51
10
38
3m
32
nod
20
11
19
12
13
nxe nye nze nip np_types
1 3 2 8 2
prop(e,v)
100.0 0.3
50.0 0.3
etype
1 2 1 2 1 2
x_coords, y_coords, z_coords
0.0 0.5
0.0 1.0 2.0 3.0
0.0 -1.0 -2.0
nr,(k,nf(:,k),i=1,nr)
46
1 0 0 1 2 1 0 1 3 1 0 1 4 0 0 1 5 1 0 1 6 0 0 1
7 1 0 1 8 1 0 1 9 0 0 1 10 1 0 1 11 0 0 0 12 0 0 0
13 0 0 0 14 0 1 1 16 0 1 1 18 0 0 0 19 0 0 0 20 0 1 1
23 0 1 1 25 0 1 1 28 0 1 1 30 0 0 0 31 0 0 0 32 0 0 0
33 0 1 1 35 0 1 1 37 0 0 0 38 0 0 0 39 0 1 1 42 0 1 1
44 0 1 1 47 0 1 1 49 0 0 0 50 0 0 0 51 0 0 0 52 0 1 1
54 0 1 1 56 0 0 0 57 0 0 0 58 0 1 1 61 0 1 1 63 0 1 1
66 0 1 1 68 0 0 0 69 0 0 0 70 0 0 0
loaded_nodes,(k,loads(nf(:,k)),i=1,loaded_nodes)
8
1 0.0 0.0 0.0417 2 0.0 0.0 -0.1667 3 0.0 0.0 0.0417
14 0.0 0.0 -0.1667 15 0.0 0.0 -0.1667 20 0.0 0.0 0.0417
21 0.0 0.0 -0.1667 22 0.0 0.0 0.0417
fixed_freedoms
0
Figure 5.24 Mesh and data for Program 5.3 example
