PressureDependent_Elastic.cppGo to the documentation of this file.00001 00002 // COPYLEFT (C): Woody's viral GPL-like license (by BJ): 00003 // ``This source code is Copyrighted in 00004 // U.S., for an indefinite period, and anybody 00005 // caught using it without our permission, will be 00006 // mighty good friends of ourn, cause we don't give 00007 // a darn. Hack it. Compile it. Debug it. Run it. 00008 // Yodel it. Enjoy it. We wrote it, that's all we 00009 // wanted to do.'' 00010 // 00011 // 00012 // COPYRIGHT (C): :-)) 00013 // PROJECT: Object Oriented Finite Element Program 00014 // FILE: 00015 // CLASS: 00016 // MEMBER FUNCTIONS: 00017 // 00018 // MEMBER VARIABLES 00019 // 00020 // PURPOSE: 00021 // 00022 // RETURN: 00023 // VERSION: 00024 // LANGUAGE: C++ 00025 // TARGET OS: 00026 // DESIGNER: Zhao Cheng, Boris Jeremic 00027 // PROGRAMMER: Zhao Cheng, 00028 // DATE: Fall 2005 00029 // UPDATE HISTORY: 00030 // 00032 // 00033 00034 // This is based on E = E0*(p/p_ref)^m 00035 // 00036 // Parameters: 00037 // 1: E0: Young's modulus when p at p_ref; 00038 // 2: v: Poissoin's ratio; 00039 // 3: m: power factor, usually = 0.5; 00040 // 4: p_ref rerefence pressure; 00041 // 5: k_cut cut-off factor, when E = k_c *E0, E = k_c*E0; 00042 00043 #ifndef PressureDependent_Elastic_CPP 00044 #define PressureDependent_Elastic_CPP 00045 00046 #include "PressureDependent_Elastic.h" 00047 00048 PressureDependent_Elastic::PressureDependent_Elastic(int E0_in, 00049 int v_in, 00050 int m_in, 00051 int p_ref_in, 00052 int k_cut_in, 00053 const stresstensor& initialStress, 00054 const straintensor& initialStrain) 00055 : ElasticState(initialStress, initialStrain), 00056 E0_index(E0_in), 00057 v_index(v_in), 00058 m_index(m_in), 00059 p_ref_index(p_ref_in), 00060 k_cut_index(k_cut_in) 00061 { 00062 00063 } 00064 00065 // Create a new 00066 ElasticState* PressureDependent_Elastic::newObj() 00067 { 00068 ElasticState * Els = new PressureDependent_Elastic(this->E0_index, 00069 this->v_index, 00070 this->m_index, 00071 this->p_ref_index, 00072 this->k_cut_index, 00073 this->Stress, 00074 this->Strain); 00075 return Els; 00076 } 00077 00078 // Get Stiffness Tensor 00079 const BJtensor& PressureDependent_Elastic::getElasticStiffness (const MaterialParameter &MaterialParameter_in) const 00080 { 00081 // Kronecker delta tensor 00082 BJtensor I2("I", 2, def_dim_2); 00083 00084 BJtensor I_ijkl = I2("ij")*I2("kl"); 00085 I_ijkl.null_indices(); 00086 BJtensor I_ikjl = I_ijkl.transpose0110(); 00087 BJtensor I_iljk = I_ijkl.transpose0111(); 00088 BJtensor I4s = (I_ikjl+I_iljk)*0.5; 00089 00090 double E0 = getE0(MaterialParameter_in); 00091 double v = getv(MaterialParameter_in); 00092 if (v >= 0.5 || v < -1.0) { 00093 opserr << "Warning!! PressureDependent_Elastic: Invalid possoin's ratio. " << endln; 00094 exit (1); 00095 } 00096 double m = getm(MaterialParameter_in); 00097 double p_ref = getp_ref(MaterialParameter_in); 00098 if ( p_ref <= 0.0) { 00099 opserr << "Warning!! PressureDependent_Elastic: Invalid reference pressure. " << endln; 00100 exit (1); 00101 } 00102 double k_cut = getk_cut(MaterialParameter_in); 00103 00104 double p = this->getStress().p_hydrostatic(); 00105 00106 double E_cut = E0 * k_cut; 00107 double E_cal = E0 * pow((p/p_ref), m); 00108 double E = (E_cal > E_cut) ? E_cal : E_cut; 00109 00110 double K = E / ( 3.0*(1.0-2.0*v) ) ; 00111 double G = E / ( 2.0*(1.0+v) ); 00112 00113 // Building elasticity tensor 00114 ElasticState::ElasticStiffness = I_ijkl *(K - 2.0*G/3.0) + I4s *(2.0*G); 00115 00116 return ElasticState::ElasticStiffness; 00117 } 00118 00119 // Get E0 00120 double PressureDependent_Elastic::getE0(const MaterialParameter &MaterialParameter_in) const 00121 { 00122 if ( E0_index > MaterialParameter_in.getNum_Material_Parameter() || E0_index < 2) { 00123 opserr << "PressureDependent_Elastic: Invalid Input. " << endln; 00124 exit (1); 00125 } 00126 else 00127 return MaterialParameter_in.getMaterial_Parameter(E0_index - 1); 00128 } 00129 00130 // Get v 00131 double PressureDependent_Elastic::getv(const MaterialParameter &MaterialParameter_in) const 00132 { 00133 if ( v_index > MaterialParameter_in.getNum_Material_Parameter() || v_index < 2) { 00134 opserr << "PressureDependent_Elastic: Invalid Input. " << endln; 00135 exit (1); 00136 } 00137 else 00138 return MaterialParameter_in.getMaterial_Parameter(v_index - 1); 00139 } 00140 00141 // Get m 00142 double PressureDependent_Elastic::getm(const MaterialParameter &MaterialParameter_in) const 00143 { 00144 if ( m_index > MaterialParameter_in.getNum_Material_Parameter() || m_index < 2) { 00145 opserr << "PressureDependent_Elastic: Invalid Input. " << endln; 00146 exit (1); 00147 } 00148 else 00149 return MaterialParameter_in.getMaterial_Parameter(m_index - 1); 00150 } 00151 00152 // Get p_ref 00153 double PressureDependent_Elastic::getp_ref(const MaterialParameter &MaterialParameter_in) const 00154 { 00155 if ( p_ref_index > MaterialParameter_in.getNum_Material_Parameter() || p_ref_index < 2) { 00156 opserr << "PressureDependent_Elastic: Invalid Input. " << endln; 00157 exit (1); 00158 } 00159 else 00160 return MaterialParameter_in.getMaterial_Parameter(p_ref_index - 1); 00161 } 00162 00163 // Get p_cut 00164 double PressureDependent_Elastic::getk_cut(const MaterialParameter &MaterialParameter_in) const 00165 { 00166 if ( k_cut_index > MaterialParameter_in.getNum_Material_Parameter() || k_cut_index < 2) { 00167 opserr << "PressureDependent_Elastic: Invalid Input. " << endln; 00168 exit (1); 00169 } 00170 else 00171 return MaterialParameter_in.getMaterial_Parameter(k_cut_index - 1); 00172 } 00173 00174 #endif 00175
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