mW = SlopeModel[<|"Points" -> {{-40., 20.}, {-20., 20.}, {-0.5, 10.}, {30., 10.}}|>,
<|"Regions" -> {
<|"Name" -> "Clay", "Base" -> 3.5, "UnitWeight" -> 20.,
"Cohesion" -> 15., "FrictionAngle" -> 25. Degree|>,
<|"Name" -> "Soft clay", "Base" -> 3.0, "UnitWeight" -> 20.,
"Cohesion" -> 20., "FrictionAngle" -> 0.|>,
<|"Name" -> "Clay", "Base" -> Automatic, "UnitWeight" -> 20.,
"Cohesion" -> 15., "FrictionAngle" -> 25. Degree|>}|>];
LayerInterfaceTable[mW]