diff --git a/GluLamb/Structure/Connection.cs b/GluLamb/Structure/Connection.cs
index 74badbc..1588115 100644
--- a/GluLamb/Structure/Connection.cs
+++ b/GluLamb/Structure/Connection.cs
@@ -31,6 +31,12 @@ public Connection(Element eleA, Element eleB, double positionA, double positionB
             Name = name;
         }
 
+        public static void Disconnect(Connection conn)
+        {
+            conn.ElementA.Connections.Remove(conn);
+            conn.ElementB.Connections.Remove(conn);
+        }
+
         public Line Discretize()
         {
             return new Line(
diff --git a/GluLamb/Structure/Element.cs b/GluLamb/Structure/Element.cs
index 22c348a..f1da46e 100644
--- a/GluLamb/Structure/Element.cs
+++ b/GluLamb/Structure/Element.cs
@@ -12,12 +12,14 @@ public class Element
         public string Name;
         public List<Connection> Connections;
         protected Plane m_plane;
+        public GeometryBase Geometry;
 
         public Element(string name = "")
         {
             Connections = new List<Connection>();
             Name = name;
             m_plane = Plane.WorldXY;
+            Geometry = null;
         }
 
         public Element(Plane handle, string name = "")
@@ -66,7 +68,6 @@ public Element GetConnected(int index)
             if (conn.ElementA == this)
                 return conn.ElementB;
             return conn.ElementA;
-
         }
     }
 
diff --git a/GluLamb/Structure/ElementGroup.cs b/GluLamb/Structure/ElementGroup.cs
index e5a46a5..420f1c8 100644
--- a/GluLamb/Structure/ElementGroup.cs
+++ b/GluLamb/Structure/ElementGroup.cs
@@ -6,15 +6,20 @@
 
 namespace GluLamb
 {
-    public class ElementGroup
+    public class ElementGroup: List<Element>
     {
         public string Name;
-        private List<Element> m_elements;
+        //private List<Element> m_elements;
 
         public ElementGroup(string name = "ElementGroup")
         {
             Name = name;
-            m_elements = new List<Element>();
+            //m_elements = new List<Element>();
+        }
+        /*
+        public int Count
+        {
+            get { return m_elements.Count; }
         }
 
         public Element this[int key]
@@ -38,5 +43,6 @@ public void Clear()
         {
             m_elements.Clear();
         }
+        */
     }
 }
diff --git a/GluLamb/Structure/Structure.cs b/GluLamb/Structure/Structure.cs
index b2349cd..baabe72 100644
--- a/GluLamb/Structure/Structure.cs
+++ b/GluLamb/Structure/Structure.cs
@@ -10,11 +10,13 @@ public class Structure
     {
         public List<Connection> Connections;
         public List<Element> Elements;
+        public Dictionary<string, List<Element>> Groups;
 
         public Structure()
         {
             Connections = new List<Connection>();
             Elements = new List<Element>();
+            Groups = new Dictionary<string, List<Element>>();
         }
 
         public static Structure FromBeamElements(List<BeamElement> elements, double searchDistance, double overlapDistance)