Steel Connection Design

Steel Connection Design

There are also American steel codes ASD and LRFD as well as the Polish code PN-90/B-03200 available in the program, however, verification of a steel connection is performed in the ESOP program. After selecting American codes or the Polish code (the option Job Preferences / Codes), choosing the bars to be connected and creating a connection (i.e. pressing the Create button in the Connection Definition dialog box), an additional dialog box is displayed on screen, in which the connection type should be selected. Once the connection type is selected and the OK button pressed, the appropriate sheet of the ESOP system - relevant for verification of the selected connection type, is activated.

Sections of the bars forming a connection as well as the forces acting on a connection are forwarded to the sheet.

NOTE: For the link between the Robot and ESOP programs to be operational, both programs needs to be installed on disk. If the ESOP system is not available, then while trying to create the link (verification according to the requirements of American codes or the Polish code), the user receives the message informing that the ESOP system has to be installed.

The following connection types are available in Robot:

To start connection definition in the structure:

select the bars forming the connection (selected bars will be highlighted in the graphic editor)

press the Create button in the Connection Definition dialog box. The appropriate type (frame knee, beam-beam, column-base etc.) will be automatically assigned to the connection. Additionally, appropriate options for the selected connection type will appear in the Connection Definition dialog box.

define appropriate parameters for the selected connection type.

The following parameters can be defined for the selected connection types:

NOTE: If a connection has been defined, there is a possibility of modifying the connection type. This is accomplished by means of the icons available in the Connection type change toolbar :

To start connection calculations, once the connection and its parameters are defined, either click on the Connection viewer and select Analysis/Calculations or choose the Analysis/Manual Verification option.

NOTE:    In case of connection verification the dialog box appearing on the screen depends on the connection type.

After entering the connection internal force values, a given connection type will be verified.

NOTE: In case of a pinned column base compared to a fixed column base, the above dialog box has a slightly different form.

The dialog box shown below contains the basic data and verification results of connections defined in the structure. The Connection Definition - data/simplified results is presented in the lower portion of the screen (under the Connection Definition) dialog box after selecting the CONNECTIONS layout.

After calculating (verifying) the connection, the Connection Definition - data/simplified results dialog box (shown below) will contain the following data:

connection number

connection type: beam-to-beam connection (B-T-B), knee connection (frame knee, beam-to-column connection or beam-to-column (two-sided) connection) (KNEE or KNEE2), fixed column base (FIX), pinned column base (PINN), concrete column base (CONC), connection with angles (ANGLE), pipe connection (TUBE) and connection using gusset plate (GUSS)

bars that make up the created connection

node, for which the connection has been created

ratio - indicator defining the maximum straining of connection elements (bolts, sheet, welds, etc.). The number determines the least favorable relation between the ratio within the connection element and the capacity of the connection element. Once the connection is calculated, the table column displays information indicating whether the connection meets the code requirements (symbol ), or does not meet the requirements (symbol

After pressing the Note button, there appears an additional dialog box in which the user may select the calculation note type (a simple one contains the table with basic info about the connection, whereas the full one contains all the code requirements checked during connection calculations).

If the bar section in a connection has been changed, then, pressing the Change button allows one to up-date the geometry of the designed structure (bar section will be exchanged in structure model). One should pay attention to the fact, that such change usually results in the necessity of recalculating the structure.

In the current program version the user may also assign a defined connection to other structure nodes (it must be a similar connection type). In order to do that, the user should:

select (highlight) the connection to be copied

select appropriate structure bars

while being in the connection viewer, select the following option from the menu: Geometry / Connection Copy.

Once these operations are performed, the connection (together with the current parameters) is copied; sections, materials and angles of inclination relevant to this "new" connection are now taken into account.

Further on there are drawings presented that show forces occurring in steel connections as well as directions of force operation for all connection types available within the Robot program.