# M. To check for and remove duplicate entities

To detect the presence of and remove instances of nodes, beams, plates, etc. which are duplicates, use the following procedure.

One definition of duplicate nodes is that they are 2 or more nodes, having distinct node numbers, but the same X, Y, Z coordinates. For example, if node number 5 has coordinates of (7, 10, 0), and node 83 also has coordinates of (7, 10, 0), node 5 and 83 are considered duplicate. However, STAAD.Pro allows you to expand the definition of this term to include nodes separated by any distance. When this menu is selected, the following message box pops up, asking the user to specify a tolerance.

Duplicate members are 2 or more members, having distinct member numbers, but connected between the same 2 nodes. For example, if there are 3 members, say, 17, 46 and 75, all connected between the nodes 105 and 117, those 3 members are considered duplicate. The order of the node incidence is disregarded during this check. For example, if member 17 has 105 as its first node, 117 as its second, and member 46 has 117 as its first node, 105 as its second, they are still treated as duplicate.

A similar definition is applicable for duplicate triangular or quadrilateral plates. Plates are considered duplicates if they share the same vertex nodes, regardless of order.

1. Depending on the entity type you are checking, select one of the following tools from the Utilities ribbon tab in the Geometry Tools group:
To check for duplicate… Select the following tool…
Nodes Node Tools > Duplicate Nodes
Beams Beam Tools > Duplicate Beams
Plates Plate Tools > Duplicate Plates
(Nodes only) The Remove Duplicate Nodes dialog opens.
2. (Nodes only) Type a distance in the Enter Tolerance field and click the OK.

The tolerance is the value used to define the distanced at which nodes are to be considered separate or a duplicate. In some cases, the process of creating the model can result in nodes that a minuscule distance apart. Specifying a tolerance greater than zero allows the program to consider those nodes as duplicates and allows you to process them as needed.

The program reviews the model for any duplicates of the selected model element type (using the tolerance for Nodes).

If no duplicates are found, a message is displayed.

If duplicates are detected, the List of Duplicate Nodes / Members / Plates dialog opens. Each entry in the list contains two or more entities that the program has detected to be duplicates.

3. Either:

click Remove All Duplicates to remove the second and additional duplicate for item in the list and then click OK to confirm the deletion

or

select individual duplicate items to retain as follows:

1. Select a duplicate set in the list and then click Retain >> to remove the duplicate from the model. The Select Node / Member / Plate dialog opens.
2. Select which item to remove:
Option Description
For nodes… Either choose the node for deletion, either by clicking it, the first in the list, or the last in the list.
For beams and plates… Select the Member / Plate To Keep drop-down list.
3. Click OK. The remaining duplicates are removed and other model entities which refer to those duplicates now reference the selected (merged) entity.
4. Repeat steps 3a through 3c as necessary to review all duplicates of the entity type selected.
4. Click Close.