Removed von Mises strain softening of phi. Cleaned up format.

src/vrm.f90

@@ -66,16 +66,6 @@ select case (trim(plasticity_type))
 
   case ('vM')
     yield = plasticity_parameters(1)
-    ! strain softening
-    strain_soft_in=plasticity_parameters(3)
-    if (strain_soft_in.gt.0.d0) then
-      strain_soft_out=plasticity_parameters(4)
-      strain_soft_yield=plasticity_parameters(2)
-      if (straintot.gt.strain_soft_in) then
-        yield = (strain_soft_yield-yield)/(strain_soft_out-strain_soft_in)*(straintot-strain_soft_out) + strain_soft_yield
-        yield = max(yield, strain_soft_yield)
-      end if
-    end if
     fail = 2.d0*viscosity*e2d-yield
     if (fail.gt.0.d0) then
       viscosity=0.5d0*yield/e2d
@@ -210,7 +200,9 @@ select case (trim(plasticity_type))
       endif
     endif
     c     = plasticity_parameters(2)
-    yield = max(c/compressibility,c-tan(phi)*pressure)
+    alpha = tan(phi)
+    k     = c
+    yield = max(c/compressibility,k-alpha*pressure)
     fail  = 2.d0*viscosity*e2d-yield
     if (fail.gt.0.d0) then
       viscosity=0.5d0*yield/e2d
@@ -233,9 +225,9 @@ select case (trim(plasticity_type))
       endif
     endif
     c = plasticity_parameters(2)
-    sin_phi=sin(phi)
-    cos_phi=cos(phi)
-    yield = max(plasticity_parameters(2)/compressibility,-pressure*sin_phi+c*cos_phi)
+    alpha = sin(phi)
+    k     = c*cos(phi)
+    yield = max(plasticity_parameters(2)/compressibility,k-alpha*pressure)
     fail  = 2.d0*viscosity*e2d-yield 
     if (fail.gt.0.d0) then
       viscosity=0.5d0*yield/e2d