RemoveUnderlying property for primitives was added

StructureHelperCommon/Models/Forces/ForceTuple.cs

@@ -1,4 +1,6 @@
-namespace StructureHelperCommon.Models.Forces
+using System.ComponentModel.DataAnnotations;
+
+namespace StructureHelperCommon.Models.Forces
 {
     /// <inheritdoc/>
     public class ForceTuple : IForceTuple
@@ -22,5 +24,17 @@
             IForceTuple forceTuple = new ForceTuple() { Mx = Mx, My = My, Nz = Nz, Qx = Qx, Qy = Qy, Mz = Mz};
             return forceTuple;
         }
+        public static ForceTuple operator +(ForceTuple first) => first;
+        public static ForceTuple operator +(ForceTuple first, ForceTuple second)
+        {
+            var result = new ForceTuple();
+            result.Mx += first.Mx + second.Mx;
+            result.My += first.My + second.My;
+            result.Mz += first.Mz + second.Mz;
+            result.Qx += first.Qx + second.Qx;
+            result.Qy += first.Qy + second.Qy;
+            result.Nz += first.Nz + second.Nz;
+            return result;
+        }
     }
 }