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STAAD.Pro GROUP Command Explained with Examples

STAAD.Pro GROUP Command Explained with Examples


 The STAAD.Pro GROUP command is used to organize joints, members, elements, and other structural components into named groups. It is particularly useful in large STAAD.Pro models where repeatedly entering long lists of member or joint numbers can make the input file difficult to read and manage.

For example, instead of repeatedly using:

101 TO 120

you can create a meaningful group such as:

_BEAMS

and use the group where supported by STAAD.Pro commands.

This article explains the STAAD.Pro GROUP command, its basic syntax, examples, group naming, and common mistakes.


What is the GROUP Command in STAAD.Pro?

The GROUP command allows you to assign structural entities to a user-defined group name.

A group can be created for different types of entities, including:

  • Members

  • Joints

  • Elements

  • Solids

  • Floors

For structural modeling, common examples include:

_COLUMNS _MAIN_BEAMS _SECONDARY_BEAMS _BRACING _BASE_NODES

Using meaningful group names makes a STAAD.Pro input file easier for another engineer to understand and modify.


STAAD.Pro GROUP Command Syntax

The basic syntax is:

START GROUP DEFINITION MEMBER _BEAMS 101 TO 120 END GROUP DEFINITION

Here:

  • START GROUP DEFINITION starts the group-definition section.

  • MEMBER specifies that the group contains members.

  • _BEAMS is the user-defined group name.

  • 101 TO 120 specifies the members included in the group.

  • END GROUP DEFINITION closes the definition section.

A key point is that STAAD.Pro group names begin with an underscore (_).


Example: Creating a Beam Group

Suppose members 101 to 120 represent beams in your structural model.

Instead of repeatedly writing:

101 TO 120

you can define:

START GROUP DEFINITION MEMBER _BEAMS 101 TO 120 END GROUP DEFINITION

The group _BEAMS now represents members 101 to 120.

This is especially useful when the same set of members needs to be referenced in multiple places.


Example: Creating Multiple Member Groups

You can define several groups within the same group-definition section.

For example:

START GROUP DEFINITION MEMBER _COLUMNS 1 TO 20 _MAIN_BEAMS 21 TO 50 _BRACING 51 TO 70 END GROUP DEFINITION

The model now contains three named groups:

  • _COLUMNS → Members 1 to 20

  • _MAIN_BEAMS → Members 21 to 50

  • _BRACING → Members 51 to 70

This is much easier to understand than a STAAD.Pro file containing unexplained member-number ranges.


Grouping Joints in STAAD.Pro

The GROUP command can also be used for joints.

For example, if joints 1 to 10 represent the base nodes of a structure:

START GROUP DEFINITION JOINT _BASE_NODES 1 TO 10 END GROUP DEFINITION

The group _BASE_NODES can then be referenced where STAAD.Pro accepts a joint group.

This approach is useful when particular nodes are repeatedly used for model operations.


Grouping Elements

For models containing plate or other finite elements, elements can also be grouped.

For example:

START GROUP DEFINITION ELEMENT _SLAB_ELEMENTS 101 TO 150 END GROUP DEFINITION

Here, _SLAB_ELEMENTS represents elements 101 to 150.

The exact application of an element group depends on the STAAD.Pro command in which the group is subsequently referenced.


Why Use Groups in STAAD.Pro?

The main advantage of the GROUP command is organization and reuse.

Consider a large industrial structure containing hundreds of members. You may have separate sets of:

  • Columns

  • Main beams

  • Secondary beams

  • Bracing members

  • Truss members

Writing long member lists repeatedly increases the chance of mistakes.

Compare:

1 TO 20 35 TO 48 62 65 TO 75

with:

_COLUMNS

The second is immediately understandable.

Groups can therefore make a STAAD.Pro input file clearer, easier to review, and easier to maintain.


GROUP vs SELECT in STAAD.Pro

GROUP and SELECT are not the same command.

The GROUP command creates a named collection of structural entities.

For example:

START GROUP DEFINITION MEMBER _BEAMS 101 TO 120 END GROUP DEFINITION

Here, _BEAMS is a named group.

The SELECT command, on the other hand, is used in a different command context for selecting entities. Therefore, GROUP should not be treated simply as another form of SELECT.

A separate article on STAAD.Pro GROUP vs SELECT is useful because this distinction is a common source of confusion for beginners.


Best Practices for Naming STAAD.Pro Groups

Use names that immediately explain what the group contains.

Good examples

_COLUMNS _MAIN_BEAMS _SECONDARY_BEAMS _BRACING _BASE_NODES _SLAB_ELEMENTS

Avoid meaningless names

_A _B _GROUP1 _GROUP2

A good naming system becomes increasingly important as the STAAD.Pro model becomes larger.

You can also use project-specific naming conventions such as:

_LEVEL1_BEAMS _LEVEL2_BEAMS _EAST_COLUMNS _WEST_COLUMNS

The exact naming convention is less important than using it consistently throughout the model.


Common STAAD.Pro GROUP Command Mistakes

1. Forgetting the underscore

A group name should begin with an underscore.

Use:

_BEAMS

rather than simply:

BEAMS

2. Using GROUP without the definition block

A typical group definition should be placed between:

START GROUP DEFINITION

and:

END GROUP DEFINITION

3. Creating too many overlapping groups

Overlapping groups can make a model harder to understand, particularly when the same members are included in several groups for different purposes.

Create groups based on a clear engineering or modeling requirement.

4. Confusing GROUP with PMEMBER

The GROUP command should not be confused with PMEMBER (Physical Member). They serve different purposes in STAAD.Pro. A group is a named collection of entities, whereas a physical member represents a different modeling concept.


STAAD.Pro GROUP Command — Quick Example

A simple practical example is:

START GROUP DEFINITION MEMBER _COLUMNS 1 TO 20 _MAIN_BEAMS 21 TO 50 _BRACING 51 TO 70 JOINT _BASE_NODES 1 TO 10 END GROUP DEFINITION

This gives the model a clear organization:

GroupEntities
_COLUMNSMembers 1–20
_MAIN_BEAMSMembers 21–50
_BRACINGMembers 51–70
_BASE_NODESJoints 1–10



Want to Understand the GROUP Command in Depth?

The examples above cover the basic use of the STAAD.Pro GROUP command. If you want to understand group definitions, syntax, different group types, practical applications, limitations, and advanced examples in more detail, read our complete guide:

→ STAAD.Pro GROUP Command - Complete In-Depth Guide



Conclusion

The STAAD.Pro GROUP command is a useful way to organize structural entities using meaningful names instead of repeatedly working with long lists of numbers.

For example:

101 TO 150

can be organized as:

_BEAMS

where the group is defined appropriately.

For small models, groups may not seem necessary. However, for large building, industrial, and steel structure models, a consistent grouping system can make the STAAD.Pro input file significantly easier to read, review, and maintain.

Next: STAAD.Pro SELECT Command Explained.