Benchmark solution ===================== Calculation method ----------------- It is an analytical solution. This test makes it possible to validate the discontinuity of the pressure of the massif, we will focus only on the theoretical resolution of the mass conservation equation: :math:`\frac{{b}^{2}}{{E}_{0}}\frac{\partial {p}_{\mathit{lq}}(y,t)}{\partial t}-\left(\frac{{K}^{\text{int}}.{k}_{\text{lq}}^{\text{rel}}}{{\mu }_{\text{lq}}^{\text{}}}\frac{{\partial }^{2}{p}_{\text{lq}}(y,t)}{\partial {y}^{2}}\right)=0` Since the above differential equation is homogeneous, with constant coefficients, the method of resolution by separable variables is used (see annex 1 for the resolution of this equation). Taking into account the initial conditions and the limits considered in paragraph :ref:`1.4 `, the expression of pore pressure for the left column is expressed by: :math:`{P}^{G}(y,t)=\frac{-{\mathrm{4F}}_{G}}{\pi b}\sum _{m=1}^{+\infty }\frac{{\left(-1\right)}^{m-1}}{\mathrm{2m}-1}{e}^{-\lambda E{\pi }^{2}{(\mathrm{2m}-1)}^{2}\frac{t}{{\mathrm{4b}}^{2}{H}^{2}}}\mathrm{cos}\left(\frac{\pi y(\mathrm{2m}-1)}{\mathrm{2H}}\right)` and the expression for pore pressure for the right column is expressed as: :math:`{P}^{D}(y,t)=\frac{-{\mathrm{4F}}_{D}}{\pi b}\sum _{m=1}^{+\infty }\frac{{\left(-1\right)}^{m-1}}{\mathrm{2m}-1}{e}^{-\lambda E{\pi }^{2}{(\mathrm{2m}-1)}^{2}\frac{t}{{\mathrm{4b}}^{2}{H}^{2}}}\mathrm{cos}\left(\frac{\pi y(\mathrm{2m}-1)}{\mathrm{2H}}\right)` Reference quantities and results ----------------------------------- Pore pressure PRE1 and stress SIYY are tested at different heights in the column and at different times. Uncertainties about the solution ---------------------------- None the solution is analytical.