Line data Source code
1 : //* This file is part of the MOOSE framework
2 : //* https://mooseframework.inl.gov
3 : //*
4 : //* All rights reserved, see COPYRIGHT for full restrictions
5 : //* https://github.com/idaholab/moose/blob/master/COPYRIGHT
6 : //*
7 : //* Licensed under LGPL 2.1, please see LICENSE for details
8 : //* https://www.gnu.org/licenses/lgpl-2.1.html
9 :
10 : #include "ComputeSmearedCrackingStress.h"
11 : #include "ElasticityTensorTools.h"
12 : #include "StressUpdateBase.h"
13 : #include "Conversion.h"
14 :
15 : registerMooseObject("SolidMechanicsApp", ComputeSmearedCrackingStress);
16 :
17 : InputParameters
18 197 : ComputeSmearedCrackingStress::validParams()
19 : {
20 197 : InputParameters params = ComputeMultipleInelasticStress::validParams();
21 197 : params.addClassDescription("Compute stress using a fixed smeared cracking model");
22 394 : params.addRequiredParam<std::vector<MaterialName>>(
23 : "softening_models",
24 : "The material objects used to compute softening behavior for loading a crack."
25 : "Either 1 or 3 models must be specified. If a single model is specified, it is"
26 : "used for all directions. If 3 models are specified, they will be used for the"
27 : "3 crack directions in sequence");
28 394 : params.addRequiredCoupledVar(
29 : "cracking_stress",
30 : "The stress threshold beyond which cracking occurs. Negative values prevent cracking.");
31 197 : MultiMooseEnum direction("x y z");
32 394 : params.addParam<MultiMooseEnum>(
33 : "prescribed_crack_directions", direction, "Prescribed directions of first cracks");
34 394 : params.addParam<unsigned int>(
35 394 : "max_cracks", 3, "The maximum number of cracks allowed at a material point.");
36 394 : params.addRangeCheckedParam<Real>("cracking_neg_fraction",
37 : 0,
38 : "cracking_neg_fraction <= 1 & cracking_neg_fraction >= 0",
39 : "The fraction of the cracking strain at which "
40 : "a transition begins during decreasing "
41 : "strain to the original stiffness.");
42 394 : params.addParam<Real>(
43 : "max_stress_correction",
44 394 : 1.0,
45 : "Maximum permitted correction to the predicted stress as a ratio of the "
46 : "stress change to the predicted stress from the previous step's damage level. "
47 : "Values less than 1 will improve robustness, but not be as accurate.");
48 :
49 591 : params.addRangeCheckedParam<Real>(
50 : "shear_retention_factor",
51 394 : 0.0,
52 : "shear_retention_factor>=0 & shear_retention_factor<=1.0",
53 : "Fraction of original shear stiffness to be retained after cracking");
54 197 : params.set<std::vector<MaterialName>>("inelastic_models") = {};
55 :
56 394 : MooseEnum crackedElasticityType("DIAGONAL FULL", "DIAGONAL");
57 394 : crackedElasticityType.addDocumentation(
58 : "DIAGONAL", "Zero out terms coupling with directions orthogonal to a crack (legacy)");
59 394 : crackedElasticityType.addDocumentation(
60 : "FULL", "Consistently scale all entries based on damage (recommended)");
61 394 : params.addParam<MooseEnum>(
62 : "cracked_elasticity_type",
63 : crackedElasticityType,
64 : "Method to modify the local elasticity tensor to account for cracking");
65 :
66 197 : return params;
67 197 : }
68 :
69 148 : ComputeSmearedCrackingStress::ComputeSmearedCrackingStress(const InputParameters & parameters)
70 : : ComputeMultipleInelasticStress(parameters),
71 148 : _cracking_stress(coupledValue("cracking_stress")),
72 296 : _max_cracks(getParam<unsigned int>("max_cracks")),
73 296 : _cracking_neg_fraction(getParam<Real>("cracking_neg_fraction")),
74 296 : _shear_retention_factor(getParam<Real>("shear_retention_factor")),
75 296 : _max_stress_correction(getParam<Real>("max_stress_correction")),
76 148 : _cracked_elasticity_type(
77 148 : getParam<MooseEnum>("cracked_elasticity_type").getEnum<CrackedElasticityType>()),
78 148 : _crack_damage(declareProperty<RealVectorValue>(_base_name + "crack_damage")),
79 296 : _crack_damage_old(getMaterialPropertyOld<RealVectorValue>(_base_name + "crack_damage")),
80 148 : _crack_flags(declareProperty<RealVectorValue>(_base_name + "crack_flags")),
81 148 : _crack_rotation(declareProperty<RankTwoTensor>(_base_name + "crack_rotation")),
82 296 : _crack_rotation_old(getMaterialPropertyOld<RankTwoTensor>(_base_name + "crack_rotation")),
83 148 : _crack_initiation_strain(
84 148 : declareProperty<RealVectorValue>(_base_name + "crack_initiation_strain")),
85 148 : _crack_initiation_strain_old(
86 148 : getMaterialPropertyOld<RealVectorValue>(_base_name + "crack_initiation_strain")),
87 148 : _crack_max_strain(declareProperty<RealVectorValue>(_base_name + "crack_max_strain")),
88 444 : _crack_max_strain_old(getMaterialPropertyOld<RealVectorValue>(_base_name + "crack_max_strain"))
89 : {
90 : MultiMooseEnum prescribed_crack_directions =
91 296 : getParam<MultiMooseEnum>("prescribed_crack_directions");
92 148 : if (prescribed_crack_directions.size() > 0)
93 : {
94 30 : if (prescribed_crack_directions.size() > 3)
95 0 : mooseError("A maximum of three crack directions may be specified");
96 90 : for (unsigned int i = 0; i < prescribed_crack_directions.size(); ++i)
97 : {
98 102 : for (unsigned int j = 0; j < i; ++j)
99 42 : if (prescribed_crack_directions[i] == prescribed_crack_directions[j])
100 0 : mooseError("Entries in 'prescribed_crack_directions' cannot be repeated");
101 60 : _prescribed_crack_directions.push_back(
102 60 : static_cast<unsigned int>(prescribed_crack_directions.get(i)));
103 : }
104 :
105 : // Fill in the last remaining direction if 2 are specified
106 30 : if (_prescribed_crack_directions.size() == 2)
107 : {
108 6 : std::set<unsigned int> available_dirs = {0, 1, 2};
109 18 : for (auto dir : _prescribed_crack_directions)
110 12 : if (available_dirs.erase(dir) != 1)
111 0 : mooseError("Invalid prescribed crack direction:" + Moose::stringify(dir));
112 6 : if (available_dirs.size() != 1)
113 0 : mooseError("Error in finding remaining available crack direction");
114 6 : _prescribed_crack_directions.push_back(*available_dirs.begin());
115 : }
116 : }
117 296 : if (!isParamSetByUser("cracked_elasticity_type"))
118 31 : paramWarning(
119 : "cracked_elasticity_type",
120 : "Defaulting to the legacy option of 'DIAGONAL', but the 'FULL' option is preferred");
121 :
122 147 : _local_elastic_vector.resize(9);
123 147 : }
124 :
125 : void
126 584 : ComputeSmearedCrackingStress::initQpStatefulProperties()
127 : {
128 584 : ComputeMultipleInelasticStress::initQpStatefulProperties();
129 :
130 584 : _crack_damage[_qp] = 0.0;
131 :
132 584 : _crack_initiation_strain[_qp] = 0.0;
133 584 : _crack_max_strain[_qp](0) = 0.0;
134 :
135 584 : switch (_prescribed_crack_directions.size())
136 : {
137 440 : case 0:
138 : {
139 440 : _crack_rotation[_qp] = RankTwoTensor::Identity();
140 440 : break;
141 : }
142 64 : case 1:
143 : {
144 64 : _crack_rotation[_qp].zero();
145 64 : switch (_prescribed_crack_directions[0])
146 : {
147 32 : case 0:
148 : {
149 32 : _crack_rotation[_qp](0, 0) = 1.0;
150 32 : _crack_rotation[_qp](1, 1) = 1.0;
151 32 : _crack_rotation[_qp](2, 2) = 1.0;
152 32 : break;
153 : }
154 0 : case 1:
155 : {
156 0 : _crack_rotation[_qp](1, 0) = 1.0;
157 0 : _crack_rotation[_qp](0, 1) = 1.0;
158 0 : _crack_rotation[_qp](2, 2) = 1.0;
159 0 : break;
160 : }
161 32 : case 2:
162 : {
163 32 : _crack_rotation[_qp](2, 0) = 1.0;
164 32 : _crack_rotation[_qp](0, 1) = 1.0;
165 32 : _crack_rotation[_qp](1, 2) = 1.0;
166 32 : break;
167 : }
168 : }
169 : break;
170 : }
171 0 : case 2:
172 : {
173 0 : mooseError("Number of prescribed crack directions cannot be 2");
174 : break;
175 : }
176 : case 3:
177 : {
178 320 : for (unsigned int i = 0; i < _prescribed_crack_directions.size(); ++i)
179 : {
180 : RealVectorValue crack_dir_vec;
181 240 : crack_dir_vec(_prescribed_crack_directions[i]) = 1.0;
182 240 : _crack_rotation[_qp].fillColumn(i, crack_dir_vec);
183 : }
184 : }
185 : }
186 584 : }
187 :
188 : void
189 145 : ComputeSmearedCrackingStress::initialSetup()
190 : {
191 145 : ComputeMultipleInelasticStress::initialSetup();
192 :
193 290 : if (!hasGuaranteedMaterialProperty(_elasticity_tensor_name, Guarantee::ISOTROPIC))
194 0 : mooseError("ComputeSmearedCrackingStress requires that the elasticity tensor be "
195 : "guaranteed isotropic");
196 :
197 435 : std::vector<MaterialName> soft_matls = getParam<std::vector<MaterialName>>("softening_models");
198 315 : for (auto soft_matl : soft_matls)
199 : {
200 : SmearedCrackSofteningBase * scsb =
201 170 : dynamic_cast<SmearedCrackSofteningBase *>(&getMaterialByName(soft_matl));
202 170 : if (scsb)
203 170 : _softening_models.push_back(scsb);
204 : else
205 0 : paramError("softening_models", "Model " + soft_matl + " is not a softening model");
206 : }
207 145 : if (_softening_models.size() == 1)
208 : {
209 : // Reuse the same model in all 3 directions
210 132 : _softening_models.push_back(_softening_models[0]);
211 132 : _softening_models.push_back(_softening_models[0]);
212 : }
213 13 : else if (_softening_models.size() != 3)
214 1 : paramError("softening_models", "Either 1 or 3 softening models must be specified");
215 144 : }
216 :
217 : void
218 640360 : ComputeSmearedCrackingStress::computeQpStress()
219 : {
220 : bool force_elasticity_rotation = false;
221 :
222 640360 : if (!previouslyCracked())
223 37800 : computeQpStressIntermediateConfiguration();
224 : else
225 : {
226 602560 : _elastic_strain[_qp] = _elastic_strain_old[_qp] + _strain_increment[_qp];
227 :
228 : // Propagate behavior from the (now inactive) inelastic models
229 602560 : _inelastic_strain[_qp] = _inelastic_strain_old[_qp];
230 602560 : for (auto model : _models)
231 : {
232 0 : model->setQp(_qp);
233 0 : model->propagateQpStatefulProperties();
234 : }
235 :
236 : // Since the other inelastic models are inactive, they will not limit the time step
237 602560 : _material_timestep_limit[_qp] = std::numeric_limits<Real>::max();
238 :
239 : // update _local_elasticity_tensor based on cracking state in previous time step
240 602560 : updateLocalElasticityTensor();
241 :
242 : // Calculate stress in intermediate configuration
243 602560 : _stress[_qp] = _local_elasticity_tensor * _elastic_strain[_qp];
244 :
245 602560 : _Jacobian_mult[_qp] = _local_elasticity_tensor;
246 : force_elasticity_rotation = true;
247 : }
248 :
249 : // compute crack status and adjust stress
250 640360 : updateCrackingStateAndStress();
251 :
252 640360 : if (_perform_finite_strain_rotations)
253 : {
254 640360 : finiteStrainRotation(force_elasticity_rotation);
255 640360 : _crack_rotation[_qp] = _rotation_increment[_qp] * _crack_rotation[_qp];
256 : }
257 640360 : }
258 :
259 : void
260 602560 : ComputeSmearedCrackingStress::updateLocalElasticityTensor()
261 : {
262 : const Real youngs_modulus =
263 602560 : ElasticityTensorTools::getIsotropicYoungsModulus(_elasticity_tensor[_qp]);
264 :
265 : bool cracking_locally_active = false;
266 :
267 602560 : const Real cracking_stress = _cracking_stress[_qp];
268 :
269 602560 : if (cracking_stress > 0)
270 : {
271 : RealVectorValue stiffness_ratio_local(1.0, 1.0, 1.0);
272 602560 : const RankTwoTensor & R = _crack_rotation_old[_qp];
273 602560 : RankTwoTensor ePrime(_elastic_strain_old[_qp]);
274 602560 : ePrime.rotate(R.transpose());
275 :
276 2410240 : for (unsigned int i = 0; i < 3; ++i)
277 : {
278 : // Update elasticity tensor based on crack status of the end of last time step
279 1807680 : if (_crack_damage_old[_qp](i) > 0.0)
280 : {
281 636336 : if (_cracking_neg_fraction == 0.0 && MooseUtils::absoluteFuzzyLessThan(ePrime(i, i), 0.0))
282 77248 : stiffness_ratio_local(i) = 1.0;
283 0 : else if (_cracking_neg_fraction > 0.0 &&
284 559088 : ePrime(i, i) < _crack_initiation_strain_old[_qp](i) * _cracking_neg_fraction &&
285 : ePrime(i, i) > -_crack_initiation_strain_old[_qp](i) * _cracking_neg_fraction)
286 : {
287 : const Real etr = _cracking_neg_fraction * _crack_initiation_strain_old[_qp](i);
288 0 : const Real Eo = cracking_stress / _crack_initiation_strain_old[_qp](i);
289 0 : const Real Ec = Eo * (1.0 - _crack_damage_old[_qp](i));
290 0 : const Real a = (Ec - Eo) / (4 * etr);
291 0 : const Real b = (Ec + Eo) / 2;
292 : // Compute the ratio of the current transition stiffness to the original stiffness
293 0 : stiffness_ratio_local(i) = (2.0 * a * etr + b) / Eo;
294 : cracking_locally_active = true;
295 : }
296 : else
297 : {
298 559088 : stiffness_ratio_local(i) = (1.0 - _crack_damage_old[_qp](i));
299 : cracking_locally_active = true;
300 : }
301 : }
302 : }
303 :
304 602560 : if (cracking_locally_active)
305 : {
306 : // Update the elasticity tensor in the crack coordinate system
307 525888 : if (_cracked_elasticity_type == CrackedElasticityType::DIAGONAL)
308 : {
309 : const bool c0_coupled = MooseUtils::absoluteFuzzyEqual(stiffness_ratio_local(0), 1.0);
310 : const bool c1_coupled = MooseUtils::absoluteFuzzyEqual(stiffness_ratio_local(1), 1.0);
311 : const bool c2_coupled = MooseUtils::absoluteFuzzyEqual(stiffness_ratio_local(2), 1.0);
312 :
313 1456 : const Real c01 = (c0_coupled && c1_coupled ? 1.0 : 0.0);
314 1456 : const Real c02 = (c0_coupled && c2_coupled ? 1.0 : 0.0);
315 1456 : const Real c12 = (c1_coupled && c2_coupled ? 1.0 : 0.0);
316 :
317 1456 : const Real c01_shear_retention = (c0_coupled && c1_coupled ? 1.0 : _shear_retention_factor);
318 1456 : const Real c02_shear_retention = (c0_coupled && c2_coupled ? 1.0 : _shear_retention_factor);
319 1456 : const Real c12_shear_retention = (c1_coupled && c2_coupled ? 1.0 : _shear_retention_factor);
320 :
321 1456 : _local_elastic_vector[0] = (c0_coupled ? _elasticity_tensor[_qp](0, 0, 0, 0)
322 : : stiffness_ratio_local(0) * youngs_modulus);
323 1456 : _local_elastic_vector[1] = _elasticity_tensor[_qp](0, 0, 1, 1) * c01;
324 1456 : _local_elastic_vector[2] = _elasticity_tensor[_qp](0, 0, 2, 2) * c02;
325 1456 : _local_elastic_vector[3] = (c1_coupled ? _elasticity_tensor[_qp](1, 1, 1, 1)
326 : : stiffness_ratio_local(1) * youngs_modulus);
327 1456 : _local_elastic_vector[4] = _elasticity_tensor[_qp](1, 1, 2, 2) * c12;
328 1456 : _local_elastic_vector[5] = (c2_coupled ? _elasticity_tensor[_qp](2, 2, 2, 2)
329 : : stiffness_ratio_local(2) * youngs_modulus);
330 1456 : _local_elastic_vector[6] = _elasticity_tensor[_qp](1, 2, 1, 2) * c12_shear_retention;
331 1456 : _local_elastic_vector[7] = _elasticity_tensor[_qp](0, 2, 0, 2) * c02_shear_retention;
332 1456 : _local_elastic_vector[8] = _elasticity_tensor[_qp](0, 1, 0, 1) * c01_shear_retention;
333 : }
334 : else // _cracked_elasticity_type == CrackedElasticityType::FULL
335 : {
336 : const Real & c0 = stiffness_ratio_local(0);
337 : const Real & c1 = stiffness_ratio_local(1);
338 : const Real & c2 = stiffness_ratio_local(2);
339 :
340 524432 : const Real c01 = c0 * c1;
341 524432 : const Real c02 = c0 * c2;
342 524432 : const Real c12 = c1 * c2;
343 :
344 524720 : const Real c01_shear_retention = std::max(c01, _shear_retention_factor);
345 524432 : const Real c02_shear_retention = std::max(c02, _shear_retention_factor);
346 524432 : const Real c12_shear_retention = std::max(c12, _shear_retention_factor);
347 :
348 524432 : _local_elastic_vector[0] = _elasticity_tensor[_qp](0, 0, 0, 0) * c0;
349 524432 : _local_elastic_vector[1] = _elasticity_tensor[_qp](0, 0, 1, 1) * c01;
350 524432 : _local_elastic_vector[2] = _elasticity_tensor[_qp](0, 0, 2, 2) * c02;
351 524432 : _local_elastic_vector[3] = _elasticity_tensor[_qp](1, 1, 1, 1) * c1;
352 524432 : _local_elastic_vector[4] = _elasticity_tensor[_qp](1, 1, 2, 2) * c12;
353 524432 : _local_elastic_vector[5] = _elasticity_tensor[_qp](2, 2, 2, 2) * c2;
354 524432 : _local_elastic_vector[6] = _elasticity_tensor[_qp](1, 2, 1, 2) * c12_shear_retention;
355 524432 : _local_elastic_vector[7] = _elasticity_tensor[_qp](0, 2, 0, 2) * c02_shear_retention;
356 524432 : _local_elastic_vector[8] = _elasticity_tensor[_qp](0, 1, 0, 1) * c01_shear_retention;
357 : }
358 :
359 : // Filling with 9 components is sufficient because these are the only nonzero entries
360 : // for isotropic or orthotropic materials.
361 525888 : _local_elasticity_tensor.fillFromInputVector(_local_elastic_vector,
362 : RankFourTensor::symmetric9);
363 :
364 : // Rotate the modified elasticity tensor back into global coordinates
365 525888 : _local_elasticity_tensor.rotate(R);
366 : }
367 : }
368 : if (!cracking_locally_active)
369 76672 : _local_elasticity_tensor = _elasticity_tensor[_qp];
370 602560 : }
371 :
372 : void
373 640360 : ComputeSmearedCrackingStress::updateCrackingStateAndStress()
374 : {
375 : const Real youngs_modulus =
376 640360 : ElasticityTensorTools::getIsotropicYoungsModulus(_elasticity_tensor[_qp]);
377 :
378 : const Real poissons_ratio =
379 : ElasticityTensorTools::getIsotropicPoissonsRatio(_elasticity_tensor[_qp]);
380 :
381 640360 : Real cracking_stress = _cracking_stress[_qp];
382 :
383 640360 : if (cracking_stress > 0)
384 : {
385 : // Initializing crack states
386 640324 : _crack_rotation[_qp] = _crack_rotation_old[_qp];
387 :
388 2561296 : for (unsigned i = 0; i < 3; ++i)
389 : {
390 1920972 : _crack_max_strain[_qp](i) = _crack_max_strain_old[_qp](i);
391 1920972 : _crack_initiation_strain[_qp](i) = _crack_initiation_strain_old[_qp](i);
392 1920972 : _crack_damage[_qp](i) = _crack_damage_old[_qp](i);
393 : }
394 :
395 : // Compute crack orientations: updated _crack_rotation[_qp] based on current strain
396 : RealVectorValue strain_in_crack_dir;
397 640324 : computeCrackStrainAndOrientation(strain_in_crack_dir);
398 :
399 2561296 : for (unsigned i = 0; i < 3; ++i)
400 : {
401 1920972 : if (strain_in_crack_dir(i) > _crack_max_strain[_qp](i))
402 639496 : _crack_max_strain[_qp](i) = strain_in_crack_dir(i);
403 : }
404 :
405 : // Check for new cracks.
406 : // Rotate stress to cracked orientation.
407 640324 : const RankTwoTensor & R = _crack_rotation[_qp];
408 640324 : RankTwoTensor sigmaPrime(_stress[_qp]);
409 640324 : sigmaPrime.rotate(R.transpose()); // stress in crack coordinates
410 :
411 : unsigned int num_cracks = 0;
412 2561296 : for (unsigned int i = 0; i < 3; ++i)
413 : {
414 1920972 : if (_crack_damage_old[_qp](i) > 0.0)
415 636336 : ++num_cracks;
416 : }
417 :
418 : bool cracked(false);
419 : RealVectorValue sigma;
420 : mooseAssert(_softening_models.size() == 3, "Must have 3 softening models");
421 2561296 : for (unsigned int i = 0; i < 3; ++i)
422 : {
423 1920972 : sigma(i) = sigmaPrime(i, i);
424 :
425 1920972 : Real stiffness_ratio = 1.0 - _crack_damage[_qp](i);
426 :
427 1920972 : const bool pre_existing_crack = (_crack_damage_old[_qp](i) > 0.0);
428 1920972 : const bool met_stress_criterion = (sigma(i) > cracking_stress);
429 1920972 : const bool loading_existing_crack = (strain_in_crack_dir(i) >= _crack_max_strain[_qp](i));
430 1920972 : const bool allowed_to_crack = (pre_existing_crack || num_cracks < _max_cracks);
431 : bool new_crack = false;
432 :
433 1920972 : cracked |= pre_existing_crack;
434 :
435 : // Adjustments for newly created cracks
436 1920972 : if (met_stress_criterion && !pre_existing_crack && allowed_to_crack)
437 : {
438 : new_crack = true;
439 3928 : ++num_cracks;
440 :
441 : // Assume Poisson's ratio drops to zero for this direction. Stiffness is then Young's
442 : // modulus.
443 3928 : _crack_initiation_strain[_qp](i) = cracking_stress / youngs_modulus;
444 :
445 3928 : if (_crack_max_strain[_qp](i) < _crack_initiation_strain[_qp](i))
446 564 : _crack_max_strain[_qp](i) = _crack_initiation_strain[_qp](i);
447 : }
448 :
449 : // Update stress and stiffness ratio according to specified crack release model
450 1917044 : if (new_crack || (pre_existing_crack && loading_existing_crack))
451 : {
452 : cracked = true;
453 171180 : _softening_models[i]->computeCrackingRelease(sigma(i),
454 : stiffness_ratio,
455 : strain_in_crack_dir(i),
456 171180 : _crack_initiation_strain[_qp](i),
457 : _crack_max_strain[_qp](i),
458 : cracking_stress,
459 : youngs_modulus,
460 : poissons_ratio);
461 171180 : _crack_damage[_qp](i) = 1.0 - stiffness_ratio;
462 : }
463 :
464 1312396 : else if (cracked && _cracking_neg_fraction > 0 &&
465 1749792 : _crack_initiation_strain[_qp](i) * _cracking_neg_fraction > strain_in_crack_dir(i) &&
466 : -_crack_initiation_strain[_qp](i) * _cracking_neg_fraction < strain_in_crack_dir(i))
467 : {
468 : const Real etr = _cracking_neg_fraction * _crack_initiation_strain[_qp](i);
469 0 : const Real Eo = cracking_stress / _crack_initiation_strain[_qp](i);
470 0 : const Real Ec = Eo * (1.0 - _crack_damage_old[_qp](i));
471 0 : const Real a = (Ec - Eo) / (4.0 * etr);
472 0 : const Real b = 0.5 * (Ec + Eo);
473 0 : const Real c = 0.25 * (Ec - Eo) * etr;
474 0 : sigma(i) = (a * strain_in_crack_dir(i) + b) * strain_in_crack_dir(i) + c;
475 : }
476 : }
477 :
478 640324 : if (cracked)
479 604056 : updateStressTensorForCracking(_stress[_qp], sigma);
480 : }
481 :
482 640360 : _crack_flags[_qp](0) = 1.0 - _crack_damage[_qp](2);
483 640360 : _crack_flags[_qp](1) = 1.0 - _crack_damage[_qp](1);
484 640360 : _crack_flags[_qp](2) = 1.0 - _crack_damage[_qp](0);
485 640360 : }
486 :
487 : void
488 640324 : ComputeSmearedCrackingStress::computeCrackStrainAndOrientation(
489 : RealVectorValue & strain_in_crack_dir)
490 : {
491 : // The rotation tensor is ordered such that directions for pre-existing cracks appear first
492 : // in the list of columns. For example, if there is one existing crack, its direction is in the
493 : // first column in the rotation tensor.
494 640324 : const unsigned int num_known_dirs = getNumKnownCrackDirs();
495 :
496 640324 : if (num_known_dirs == 0)
497 : {
498 36852 : std::vector<Real> eigval(3, 0.0);
499 36852 : RankTwoTensor eigvec;
500 :
501 36852 : _elastic_strain[_qp].symmetricEigenvaluesEigenvectors(eigval, eigvec);
502 :
503 : // If the elastic strain is beyond the cracking strain, save the eigen vectors as
504 : // the rotation tensor. Reverse their order so that the third principal strain
505 : // (most tensile) will correspond to the first crack.
506 36852 : _crack_rotation[_qp].fillColumn(0, eigvec.column(2));
507 36852 : _crack_rotation[_qp].fillColumn(1, eigvec.column(1));
508 36852 : _crack_rotation[_qp].fillColumn(2, eigvec.column(0));
509 :
510 36852 : strain_in_crack_dir(0) = eigval[2];
511 36852 : strain_in_crack_dir(1) = eigval[1];
512 36852 : strain_in_crack_dir(2) = eigval[0];
513 36852 : }
514 603472 : else if (num_known_dirs == 1)
515 : {
516 : // This is easily the most complicated case.
517 : // 1. Rotate the elastic strain to the orientation associated with the known
518 : // crack.
519 : // 2. Extract the lower 2x2 block into a separate tensor.
520 : // 3. Run the eigen solver on the result.
521 : // 4. Update the rotation tensor to reflect the effect of the 2 eigenvectors.
522 :
523 : // 1.
524 325256 : const RankTwoTensor & R = _crack_rotation[_qp];
525 325256 : RankTwoTensor ePrime(_elastic_strain[_qp]);
526 325256 : ePrime.rotate(R.transpose()); // elastic strain in crack coordinates
527 :
528 : // 2.
529 325256 : ColumnMajorMatrix e2x2(2, 2);
530 325256 : e2x2(0, 0) = ePrime(1, 1);
531 325256 : e2x2(1, 0) = ePrime(2, 1);
532 325256 : e2x2(0, 1) = ePrime(1, 2);
533 325256 : e2x2(1, 1) = ePrime(2, 2);
534 :
535 : // 3.
536 325256 : ColumnMajorMatrix e_val2x1(2, 1);
537 325256 : ColumnMajorMatrix e_vec2x2(2, 2);
538 325256 : e2x2.eigen(e_val2x1, e_vec2x2);
539 :
540 : // 4.
541 : RankTwoTensor eigvec(
542 325256 : 1.0, 0.0, 0.0, 0.0, e_vec2x2(0, 1), e_vec2x2(1, 1), 0.0, e_vec2x2(0, 0), e_vec2x2(1, 0));
543 :
544 325256 : _crack_rotation[_qp] = _crack_rotation_old[_qp] * eigvec; // Roe implementation
545 :
546 325256 : strain_in_crack_dir(0) = ePrime(0, 0);
547 325256 : strain_in_crack_dir(1) = e_val2x1(1, 0);
548 325256 : strain_in_crack_dir(2) = e_val2x1(0, 0);
549 : }
550 278216 : else if (num_known_dirs == 2 || num_known_dirs == 3)
551 : {
552 : // Rotate to cracked orientation and pick off the strains in the rotated
553 : // coordinate directions.
554 278216 : const RankTwoTensor & R = _crack_rotation[_qp];
555 278216 : RankTwoTensor ePrime(_elastic_strain[_qp]);
556 278216 : ePrime.rotate(R.transpose()); // elastic strain in crack coordinates
557 :
558 278216 : strain_in_crack_dir(0) = ePrime(0, 0);
559 278216 : strain_in_crack_dir(1) = ePrime(1, 1);
560 278216 : strain_in_crack_dir(2) = ePrime(2, 2);
561 : }
562 : else
563 0 : mooseError("Invalid number of known crack directions");
564 640324 : }
565 :
566 : unsigned int
567 640324 : ComputeSmearedCrackingStress::getNumKnownCrackDirs() const
568 : {
569 : unsigned int num_known_dirs = 0;
570 2561296 : for (unsigned int i = 0; i < 3; ++i)
571 : {
572 1920972 : if (_crack_damage_old[_qp](i) > 0.0 || _prescribed_crack_directions.size() >= i + 1)
573 981120 : ++num_known_dirs;
574 : }
575 640324 : return num_known_dirs;
576 : }
577 :
578 : void
579 604056 : ComputeSmearedCrackingStress::updateStressTensorForCracking(RankTwoTensor & tensor,
580 : const RealVectorValue & sigma)
581 : {
582 : // Get transformation matrix
583 604056 : const RankTwoTensor & R = _crack_rotation[_qp];
584 : // Rotate to crack frame
585 604056 : tensor.rotate(R.transpose());
586 :
587 : // Reset stress if cracked
588 2416224 : for (unsigned int i = 0; i < 3; ++i)
589 1812168 : if (_crack_damage[_qp](i) > 0.0)
590 : {
591 638212 : const Real stress_correction_ratio = (tensor(i, i) - sigma(i)) / tensor(i, i);
592 638212 : if (stress_correction_ratio > _max_stress_correction)
593 0 : tensor(i, i) *= (1.0 - _max_stress_correction);
594 638212 : else if (stress_correction_ratio < -_max_stress_correction)
595 0 : tensor(i, i) *= (1.0 + _max_stress_correction);
596 : else
597 638212 : tensor(i, i) = sigma(i);
598 : }
599 :
600 : // Rotate back to global frame
601 604056 : tensor.rotate(R);
602 604056 : }
603 :
604 : bool
605 640360 : ComputeSmearedCrackingStress::previouslyCracked()
606 : {
607 1082160 : for (unsigned int i = 0; i < 3; ++i)
608 1044360 : if (_crack_damage_old[_qp](i) > 0.0)
609 : return true;
610 : return false;
611 : }
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