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laws:orthopla [2023/11/29 10:37]
arthur [Integer parameters]
laws:orthopla [2024/01/23 12:15] (current)
hangbiao
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  :​laws:​schematic_view_of_the_angle_between_the_normal_to_bedding_plane_and_the_direction_of_major_principal_stress.png?​150 ​ |}}</​imgcaption>​  :​laws:​schematic_view_of_the_angle_between_the_normal_to_bedding_plane_and_the_direction_of_major_principal_stress.png?​150 ​ |}}</​imgcaption>​
  
-Three cohesion values are defined ($c_{0^{\circ}},​ c_{min}, c_{90^{\circ}}$),​ for major principal stress parallel $\alpha_{\sigma_1} = 0^{\circ}$ (perpendicular),​ perpendicular $\alpha_{\sigma_1} = 90^{\circ}$ (parallel) and with an angle of $\alpha_{\sigma_1,​ min}$ with respect to the normal to bedding plane (with respect to the bedding plane). Between those values, cohesion varies linearly with $\alpha_{\sigma_1}$. The mathematical expression of the cohesion is as follows:+Three cohesion values are defined ($c_{0^{\circ}},​ c_{min}, c_{90^{\circ}}$),​ for major principal stress parallel $\alpha_{\sigma_1} = 0^{\circ}$ (perpendicular),​ perpendicular $\alpha_{\sigma_1} = 90^{\circ}$ (parallel) and with an angle of $\alpha_{\sigma_1,​ min}$ with respect to the normal to bedding plane (with respect to the bedding plane)  (Salehnia, 2015)((Salehnia,​ F. (2015) From some obscurity to clarity in Boom clay behavior: Analysis of its coupled hydro-mechanical response in the presence of strain localization. Thesis, Liège University.)). Between those values, cohesion varies linearly with $\alpha_{\sigma_1}$. The mathematical expression of the cohesion is as follows:
 \[ \[
 c = \max \left[\left( \frac{c_{min} - c_{0^{\circ}}}{\alpha_{\sigma_1,​ min}} \right)\alpha_{\sigma_1} + c_{0^{\circ}} ;  \left( \frac{c_{90^{\circ}} - c_{min}}{90^{\circ} - \alpha_{\sigma_1,​ min}} \right)\left( \alpha_{\sigma_1} - \alpha_{\sigma_1,​ min} \right)+ c_{0^{\circ}} ​ \right] c = \max \left[\left( \frac{c_{min} - c_{0^{\circ}}}{\alpha_{\sigma_1,​ min}} \right)\alpha_{\sigma_1} + c_{0^{\circ}} ;  \left( \frac{c_{90^{\circ}} - c_{min}}{90^{\circ} - \alpha_{\sigma_1,​ min}} \right)\left( \alpha_{\sigma_1} - \alpha_{\sigma_1,​ min} \right)+ c_{0^{\circ}} ​ \right]
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 Considering cross-anisotropy,​ i.e. transverse isotropy, and refering the problem to the principal material axes implies $A_{ij} = 0$ for $i \neq j$, $A_{ii} = A_{11}+A_{22}+A_{33} = 0$, $A_{11} = A_{33}$ if the bedding plane is in ($e_1, e_3$) anisotropic plane, $A_{22} = -2A_{11}$, implying : Considering cross-anisotropy,​ i.e. transverse isotropy, and refering the problem to the principal material axes implies $A_{ij} = 0$ for $i \neq j$, $A_{ii} = A_{11}+A_{22}+A_{33} = 0$, $A_{11} = A_{33}$ if the bedding plane is in ($e_1, e_3$) anisotropic plane, $A_{22} = -2A_{11}$, implying :
 \[A_{ij}l_il_j = A_{l1}(1-3l_2^2)\] \[A_{ij}l_il_j = A_{l1}(1-3l_2^2)\]
-where $A_{11}$ is the component of the microstructure operator $A_{ij}$ in the isotropic (bedding) plane. The late expression for cohesion becomes :+where $A_{11}$ is the component of the microstructure operator $A_{ij}$ in the isotropic (bedding) plane. The late expression for cohesion becomes ​(Pardoen, 2015)((Pardoen,​ B. (2015) ​ Hydro-mechanical analysis of the fracturing induced by the excavation of nuclear waste repository galleries using shear banding. Thesis, Liège University.)):
 \[c= c_0 \left( 1+A_{l1}(1-3l_2^2) + b_1A_{l1}^2(1-3l_2^2)^2 + b_2A_{l1}^3(1-3l_2^2)^3 + … \right)\] \[c= c_0 \left( 1+A_{l1}(1-3l_2^2) + b_1A_{l1}^2(1-3l_2^2)^2 + b_2A_{l1}^3(1-3l_2^2)^3 + … \right)\]
  
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 ==== Vicoplasticity ==== ==== Vicoplasticity ====
 See [[laws:​epplasol|PLASOL]] \\ See [[laws:​epplasol|PLASOL]] \\
-Remark : For anisotropic Biot’s coeffcient, the deviatoric stress ​ is calculated from the effective stresses (more details about this anisotropy are available in the definition of element CSOL2 and ISOL=9 in [[appendices:​a8|Appendix ​8]]).+Remark : For anisotropic Biot’s coeffcient, the deviatoric stress ​ is calculated from the effective stresses (more details about this anisotropy are available in the definition of element CSOL2 and ISOL=9 in [[appendices:​a7|Appendix ​7]]).
  
 ===== Availability ===== ===== Availability =====
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 |E3F|Final elastic Young modulus E($e_{3f}$)| |E3F|Final elastic Young modulus E($e_{3f}$)|
 |Gamma7|equivalent strain at which the Young'​s modulus has reduced to 0.7 times | |Gamma7|equivalent strain at which the Young'​s modulus has reduced to 0.7 times |
 +|Aa|Fitting parameter |
 ^ Line 8 (7G10.0) (Only if IECPS = 2 or 3) ^^  ^ Line 8 (7G10.0) (Only if IECPS = 2 or 3) ^^ 
-|PSICPEAK| +|PSICPEAK| Peak of dilatancy angle for compressive paths (If IECPS=2 then PSICPEAK is the initial value of dilatancy angle
-|PSICLIM| +|PSICLIM| Limit value of dilatancy angle for compressive paths
-|RATPSI| +|RATPSI| Ratio between initial and peak of dilatancy angle
-|BPSI| +|BPSI| Value of EEQU for which PSIC=0.5 (PSICPEAK - PSICLIM)  ​
-|PSIEPEAK| +|PSIEPEAK| Peak of dilatancy angle for extensive paths (If IECPS=2 then PSIEPEAK is the initial value of dilatancy angle)  ​
-|PSIELIM| +|PSIELIM| Limit value of dilatancy angle for extensive paths
-|DECPSI|+|DECPSI| Value of EEQU when the dilatancy angle has been half decreased between its initial and final values|
 ^ Line 9 (2G10.0) (Only if IDAM = 1) ^^ ^ Line 9 (2G10.0) (Only if IDAM = 1) ^^
 |P|Parameter controlling the damage evolution rate| |P|Parameter controlling the damage evolution rate|
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 |Q(34)$\rightarrow$ Q(36)| = reserved for small strain stiffness (E1, E2, E3) | |Q(34)$\rightarrow$ Q(36)| = reserved for small strain stiffness (E1, E2, E3) |
 |Q(37)$\rightarrow$ Q(48)| = reserved for bifurcation | |Q(37)$\rightarrow$ Q(48)| = reserved for bifurcation |
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laws/orthopla.1701250637.txt.gz · Last modified: 2023/11/29 10:37 by arthur