inp文件中已经删除相应单元，显示未定义属性?
part-1只留下一个PD3D单元，其余都删了，为什么还会说没定义属性
error信息：
1 elements have missing property definitions. The elements have been identified in element set ErrElemMissingSection.
inp文件：
*Heading
** Job name: Job-2 Model name: Model-1
** Generated by: Abaqus/CAE 2016
*Preprint, echo=NO, model=NO, history=NO, contact=NO
**
** PARTS
**
*Part, name=Part-1
*Node
1, 0., -10., 20.
*Element, type=PD3D, elset=node_Inertia-1_
1, 1
*DISCRETE SECTION, elset=Set-1_Inertia-1_,DENSITY=2E-9,ALPHA=0
1
*DISCRETE ELASTICITY
200000,0.3
*End Part
**
*Part, name=Part-2
*Node
1, 25., 25., 0.
2, 20., 25., 0.
3, 15., 25., 0.
4, 10., 25., 0.
5, 5., 25., 0.
6, 0., 25., 0.
7, -5., 25., 0.
8, -10., 25., 0.
9, -15., 25., 0.
10, -20., 25., 0.
11, -25., 25., 0.
12, 25., 20., 0.
13, 20., 20., 0.
14, 15., 20., 0.
15, 10., 20., 0.
16, 5., 20., 0.
17, 0., 20., 0.
18, -5., 20., 0.
19, -10., 20., 0.
20, -15., 20., 0.
21, -20., 20., 0.
22, -25., 20., 0.
23, 25., 15., 0.
24, 20., 15., 0.
25, 15., 15., 0.
26, 10., 15., 0.
27, 5., 15., 0.
28, 0., 15., 0.
29, -5., 15., 0.
30, -10., 15., 0.
31, -15., 15., 0.
32, -20., 15., 0.
33, -25., 15., 0.
34, 25., 10., 0.
35, 20., 10., 0.
36, 15., 10., 0.
37, 10., 10., 0.
38, 5., 10., 0.
39, 0., 10., 0.
40, -5., 10., 0.
41, -10., 10., 0.
42, -15., 10., 0.
43, -20., 10., 0.
44, -25., 10., 0.
45, 25., 5., 0.
46, 20., 5., 0.
47, 15., 5., 0.
48, 10., 5., 0.
49, 5., 5., 0.
50, 0., 5., 0.
51, -5., 5., 0.
52, -10., 5., 0.
53, -15., 5., 0.
54, -20., 5., 0.
55, -25., 5., 0.
56, 25., 0., 0.
57, 20., 0., 0.
58, 15., 0., 0.
59, 10., 0., 0.
60, 5., 0., 0.
61, 0., 0., 0.
62, -5., 0., 0.
63, -10., 0., 0.
64, -15., 0., 0.
65, -20., 0., 0.
66, -25., 0., 0.
67, 25., -5., 0.
68, 20., -5., 0.
69, 15., -5., 0.
70, 10., -5., 0.
71, 5., -5., 0.
72, 0., -5., 0.
73, -5., -5., 0.
74, -10., -5., 0.
75, -15., -5., 0.
76, -20., -5., 0.
77, -25., -5., 0.
78, 25., -10., 0.
79, 20., -10., 0.
80, 15., -10., 0.
81, 10., -10., 0.
82, 5., -10., 0.
83, 0., -10., 0.
84, -5., -10., 0.
85, -10., -10., 0.
86, -15., -10., 0.
87, -20., -10., 0.
88, -25., -10., 0.
89, 25., -15., 0.
90, 20., -15., 0.
91, 15., -15., 0.
92, 10., -15., 0.
93, 5., -15., 0.
94, 0., -15., 0.
95, -5., -15., 0.
96, -10., -15., 0.
97, -15., -15., 0.
98, -20., -15., 0.
99, -25., -15., 0.
100, 25., -20., 0.
101, 20., -20., 0.
102, 15., -20., 0.
103, 10., -20., 0.
104, 5., -20., 0.
105, 0., -20., 0.
106, -5., -20., 0.
107, -10., -20., 0.
108, -15., -20., 0.
109, -20., -20., 0.
110, -25., -20., 0.
111, 25., -25., 0.
112, 20., -25., 0.
113, 15., -25., 0.
114, 10., -25., 0.
115, 5., -25., 0.
116, 0., -25., 0.
117, -5., -25., 0.
118, -10., -25., 0.
119, -15., -25., 0.
120, -20., -25., 0.
121, -25., -25., 0.
*Element, type=R3D4
1, 1, 2, 13, 12
2, 2, 3, 14, 13
3, 3, 4, 15, 14
4, 4, 5, 16, 15
5, 5, 6, 17, 16
6, 6, 7, 18, 17
7, 7, 8, 19, 18
8, 8, 9, 20, 19
9, 9, 10, 21, 20
10, 10, 11, 22, 21
11, 12, 13, 24, 23
12, 13, 14, 25, 24
13, 14, 15, 26, 25
14, 15, 16, 27, 26
15, 16, 17, 28, 27
16, 17, 18, 29, 28
17, 18, 19, 30, 29
18, 19, 20, 31, 30
19, 20, 21, 32, 31
20, 21, 22, 33, 32
21, 23, 24, 35, 34
22, 24, 25, 36, 35
23, 25, 26, 37, 36
24, 26, 27, 38, 37
25, 27, 28, 39, 38
26, 28, 29, 40, 39
27, 29, 30, 41, 40
28, 30, 31, 42, 41
29, 31, 32, 43, 42
30, 32, 33, 44, 43
31, 34, 35, 46, 45
32, 35, 36, 47, 46
33, 36, 37, 48, 47
34, 37, 38, 49, 48
35, 38, 39, 50, 49
36, 39, 40, 51, 50
37, 40, 41, 52, 51
38, 41, 42, 53, 52
39, 42, 43, 54, 53
40, 43, 44, 55, 54
41, 45, 46, 57, 56
42, 46, 47, 58, 57
43, 47, 48, 59, 58
44, 48, 49, 60, 59
45, 49, 50, 61, 60
46, 50, 51, 62, 61
47, 51, 52, 63, 62
48, 52, 53, 64, 63
49, 53, 54, 65, 64
50, 54, 55, 66, 65
51, 56, 57, 68, 67
52, 57, 58, 69, 68
53, 58, 59, 70, 69
54, 59, 60, 71, 70
55, 60, 61, 72, 71
56, 61, 62, 73, 72
57, 62, 63, 74, 73
58, 63, 64, 75, 74
59, 64, 65, 76, 75
60, 65, 66, 77, 76
61, 67, 68, 79, 78
62, 68, 69, 80, 79
63, 69, 70, 81, 80
64, 70, 71, 82, 81
65, 71, 72, 83, 82
66, 72, 73, 84, 83
67, 73, 74, 85, 84
68, 74, 75, 86, 85
69, 75, 76, 87, 86
70, 76, 77, 88, 87
71, 78, 79, 90, 89
72, 79, 80, 91, 90
73, 80, 81, 92, 91
74, 81, 82, 93, 92
75, 82, 83, 94, 93
76, 83, 84, 95, 94
77, 84, 85, 96, 95
78, 85, 86, 97, 96
79, 86, 87, 98, 97
80, 87, 88, 99, 98
81, 89, 90, 101, 100
82, 90, 91, 102, 101
83, 91, 92, 103, 102
84, 92, 93, 104, 103
85, 93, 94, 105, 104
86, 94, 95, 106, 105
87, 95, 96, 107, 106
88, 96, 97, 108, 107
89, 97, 98, 109, 108
90, 98, 99, 110, 109
91, 100, 101, 112, 111
92, 101, 102, 113, 112
93, 102, 103, 114, 113
94, 103, 104, 115, 114
95, 104, 105, 116, 115
96, 105, 106, 117, 116
97, 106, 107, 118, 117
98, 107, 108, 119, 118
99, 108, 109, 120, 119
100, 109, 110, 121, 120
*Node
122, 0., -25., 0.
*Nset, nset=Part-2-RefPt_, internal
122,
*Elset, elset=Part-2, generate
1, 100, 1
*End Part
**
**
** ASSEMBLY
**
*Assembly, name=Assembly
**
*Instance, name=Part-2-1, part=Part-2
0., -15., 0.
0., -15., 0., 1., -15., 0., 90.
*End Instance
**
*Instance, name=Part-1-1, part=Part-1
*End Instance
**
*Nset, nset=Set-1, instance=Part-2-1
122,
*Nset, nset=Set-2, instance=Part-1-1, generate
1, 1, 1
*Elset, elset=Set-2, instance=Part-1-1, generate
1, 1, 1
*Rigid Body, ref node=Part-2-1.Part-2-RefPt_, elset=Part-2-1.Part-2
*End Assembly
**
**
** INTERACTION PROPERTIES
**
*SURFACE INTERACTION,NAME=IntProp-1
*SURFACE BEHAVIOR,PRESSURE-OVERCLOSURE=Hertz
9e13
**
** BOUNDARY CONDITIONS
**
** Name: BC-1 Type: Symmetry/Antisymmetry/Encastre
*Boundary
Set-1, ENCASTRE
**
** PREDEFINED FIELDS
**
** Name: Predefined Field-1 Type: Velocity
*Initial Conditions, type=VELOCITY
Set-2, 1, 0.
Set-2, 2, -100.
Set-2, 3, 0.
** ----------------------------------------------------------------
**
** STEP: Step-1
**
*Step, name=Step-1, nlgeom=YES
*Dynamic, Explicit
, 0.1
*Bulk Viscosity
0.06, 1.2
**
** INTERACTIONS
**
** Interaction: Int-1
*Contact, op=NEW
*Contact Inclusions, ALL EXTERIOR
*Contact Property Assignment
, , IntProp-1
**
** OUTPUT REQUESTS
**
*Restart, write, number interval=1, time marks=NO
**
** FIELD OUTPUT: F-Output-1
**
*Output, field, variable=PRESELECT
**
** HISTORY OUTPUT: H-Output-1
**
*Output, history, variable=PRESELECT
*End Step
cancan01 
