Force combination was added

StructureHelperCommon/Models/Forces/ForceTuple.cs

@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Models.Forces
+{
+    public class ForceTuple : IForceTuple
+    {
+        public double Mx { get; set; }
+        public double My { get; set; }
+        public double Nz { get; set; }
+        public double Qx { get; set; }
+        public double Qy { get; set; }
+        public double Mz { get; set; }
+    }
+}