[doc] LIE: Add 3D benchmark results.

web/content/docs/benchmarks/hydro-mechanics/lie-hm-linear-single-fracture.md

@@ -27,3 +27,15 @@ Result showing pore pressure increase due to the injection and subsequent fractu
 
 {{< img src="../x_p_t500.png" >}}
 {{< img src="../x_b_t500.png" >}}
+
+## 3D setup
+
+Same setup as for the given 2D case above with additional plane strain
+conditions in the front and back x-y planes.
+Warp of the 1000-times oversized displacement and the fracture's aperture are
+shown in the following figure.
+{{< img src="../single_fracture_3D.png" >}}
+
+Comparison with 2D setup yields identical results (up to numerical differences
+in order of 1e-15):
+{{< img src="../single_fracture_3D_vs_2D.png" >}}

web/content/docs/benchmarks/small-deformations/lie-m-linear-single-fracture.md

@@ -24,3 +24,12 @@ See [this PDF](../LIE_small_deformation.pdf) for detailed problem description.
 Result showing sliding of the upper part of the domain along the fracture:
 
 {{< img src="../LIE_SD_m_result_uy.png" >}}
+
+
+Same benchmark setup with plane strain conditions in 3D:
+{{< img src="../single_joint_3D.png" >}}
+
+Comparison with 2D setup yields identical results (up to numerical differences
+in order of 1e-15); Resulting displacement on the left axis, and error on the
+right:
+{{< img src="../single_joint_3D_2D_results.png" >}}