crack-abaqus.doc

Analysis of a Deep Single Edge Notch(凹口凹口) Crack in a Plate This example demonstrates the use of the “deep crack“ capability in ZENCRACK with both sides of the crack modelled. In this type of analysis, in addition to（除 此之外） inserting crack-blocks into the mesh, ZENCRACK separates（分离） other standard elements to form parts of the crack face.The example consists of a simple mesh of a square plate under prescribed（规定的） end loading (displacement boundary condition——位移边界条件). The full plate is modelled even though（虽然） the geometry and loading is symmetric（对称的）. A schematic of the geometry and loading is shown in Figure QA16-1.Figure QA16-1 - Square plate with single edge notch F.E. Mesh for the Uncracked ComponentThe finite element model for the uncracked component is shown in Figure QA16-2. The mesh consists of a 4x4x1 grid of elements. The crack is to be inserted by replacing elements 7 and 11. The nodes used to define（定义） crack orientation（方向） for each of these elements are shown in Figure QA16-3.To extend the crack faces outside the crack-blocks, it is required that elements 8 and 12 are split.ABAQUS Input Deck for the Uncracked ComponentThe ABAQUS input deck for the uncracked component is given in listing 1. The following points should be noted :1. PropertiesThe material property name ZCRMAT has been used to allow ZENCRACK to extract（提取） Young’s modulus and Poisson ratio from the uncracked mesh.ZENCRACK Input and OutputThe ZENCRACK input file is shown in listing 2. The analysis output file is shown in listing 3.The following points are specific to the “deep crack“ definition :Input record 3 : 2 2 2 0.25 1 0 1Item 7, ISPLIT, is set to 1 to indicate that one split set is to be defined.Input record 3c : 1This indicates that there is 1 element pair in the split set.Input record 3d : 8 12This indicates that elements 8 and 12 are to be split.Figure QA16-2 - Uncracked mesh - element numbers Figure QA16-3 - Uncracked mesh - element 7 and 11Nodes for crack front orientation Figure QA16-4 - Cracked mesh Figure QA16-5 - Cracked mesh - displaced plot Figure QA16-6 - Cracked mesh - “lower left“ region - displaced plot LISTING 1 File: a16uc01.inp Description: ABAQUS input file for uncracked component*HEADING QA16 - 4x4x1 mesh *PREPRINT,ECHO=NO,HISTORY=NO,MODEL=NO *RESTART,WRITE *ELEMENT,TYPE=C3D20,ELSET=EALL1 1 2 7 6 26 27 32 31 126 127 128 129 130 131 132133 134 135 136 1372 2 3 8 7 27 28 33 32 384 376 385 127 386 380 387131 135 381 383 1363 3 4 9 8 28 29 34 33 373 374 375 376 377 378 379380 381 382 371 3834 4 5 10 9 29 30 35 34 388 389 365 374 390 391 368378 382 392 372 3715 26 27 32 31 51 52 57 56 130 131 132 133 302 213 224303 402 403 404 4056 27 28 33 32 52 53 58 57 386 380 387 131 211 203 212213 403 419 421 4047 28 29 34 33 53 54 59 58 377 378 379 380 200 201 202203 419 420 417 4218 29 30 35 34 54 55 60 59 390 391 368 378 219 220 192201 420 422 418 4179 51 52 57 56 76 77 82 81 302 213 224 303 238 216 227239 304 217 218 23010 52 53 58 57 77 78 83 82 211 203 212 213 214 207 215216 217 208 210 21811 53 54 59 58 78 79 84 83 200 201 202 203 204 205 206207 208 209 198 21012 54 55 60 59 79 80 85 84 219 220 192 201 221 222 195205 209 223 199 19813 76 77 82 81 101 102 107 106 238 216 227 239 240 241 242243 244 245 246 24714 77 78 83 82 102 103 108 107 214 207 215 216 294 290 295241 245 291 293 24615 78 79 84 83 103 104 109 108 204 205 206 207 287 288 289290 291 292 285 29316 79 80 85 84 104 105 110 109 221 222 195 205 296 297 282288 292 298 286 285 *NODE1 0.0000 0.0000 0.00002 2.5000 0.0000 0.00003 5.0000 0.0000 0.00004 7.5000 0.0000 0.00005 10.0000 0.0000 0.00006 0.0000 2.5000 0.00007 2.5000 2.5000 0.00008 5.0000 2.5000 0.00009 7.5000 2.5000 0.000010 10.0000 2.5000 0.000026 0.0000 0.0000 2.500027 2.5000 0.0000 2.500028 5.0000 0.0000 2.500029 7.5000 0.0000 2.500030 10.0000 0.0000 2.500031 0.0000 2.5000 2.500032 2.5000 2.5000 2.500033 5.0000 2.5000 2.500034 7.5000 2.5000 2.500035 10.0000 2.5000 2.500051 0.0000 0.0000 5.000052 2.5000 0.0000 5.000053 5.0000 0.0000 5.000054 7.5000 0.0000 5.000055 10.0000 0.0000 5.000056 0.0000 2.5000 5.000057 2.5000 2.5000 5.000058 5.0000 2.5000 5.000059 7.5000 2.5000 5.000060 10.0000 2.5000 5.000076 0.0000 0.0000 7.500077 2.5000 0.0000 7.500078 5.0000 。