Interactive Design

Forms: Interactive Composite Beam Design and Review

Interactive composite beam design is a feature that lets you review the design results for any composite beam, select the best design from the various acceptable designs, and interactively change the design assumptions and immediately view the results.

Access Interactive Composite Beam Design and Review as follows:

Select the Analyze menu > Run Analysis command to analyze the model.
Select the Design menu > Composite Beam Design > Start Design/Check command.
Right click on a beam while the design results are displayed to enter the interactive design mode and interactively design the beam using the Interactive Composite Beam Design and Review form. If you are not currently displaying design results, click the Design menu > Composite Beam Design > Interactive Design command and then right click a beam to enter the interactive design mode for that beam.
Use the Interactive Composite Beam Design and Review form to complete the interactive design and review: The form is divided into two sides. The items on the left side of the form, which include a list of acceptable designs from which you can choose, let you control the beam design. The items on the right side of the form display information on the beam and the selected design, or let you access more detailed information.

Use the left side of the form to control the beam design:

When the beam is assigned an auto select list, the Acceptable Designs list shows the various designs generated for all the sections in the auto select list. When a beam is assigned a specific section instead, the list is limited to the one design generated for that section.

A design consists of a section, shear stud distribution. camber, and a number of design checks that all must be satisfied for the design to be acceptable. Deflection, vibration, shear, positive and negative moment design checks are performed for all the considered design load combinations. Unless the beam is shored during construction, the design loads and load combinations must consider construction loading. The list of designs shows each section name, shear stud distribution, camber, and controlling stress ratio. The controlling ratio is the largest of the design ratios evaluated in each of the design checks.

When a design is selected from the list, the details of the design checks are shown on the right side of the form. If you click OK and the selected design differs from the initial beam design, you will be asked if you want to apply the selected design to the beam. If you choose to do so and the beam is part of a group and and that design group was considered in the design of the beam, all the beams in the design group will also be redesigned. If the beam is not part of a design group, but there are stories similar to the story it is on and the Similar Stories mode or All Stories mode is active, all the beams in the same location on similar stories, or on all stories depending on the mode, will also be redesigned.

You may on occasion wonder why there is no design showing for a given section. The Show All Alternates toggle lets you view all the designs generated for the beam, even those that aren’t acceptable. When you select Show All Alternates, the Acceptable Designs area is renamed Alternate Designs and designs that aren’t acceptable show up in red. Also, when none of the designs considered for the beam is acceptable, the Show All Alternates toggle is automatically checked and all the designs are listed – in red.
When the selected beam is part of a design group and that design group was considered in the design of the beam, a design is acceptable if it meets all the design criteria for all the beams in the group. However, the controlling ratio shown for each design is the controlling ratio computed when checking only the selected beam and the design checks displayed on the right are the design checks done for the selected beam. To look instead at the highest controlling ratios computed ffor each design when checking all the beams in the group, check the Show Group Results toggle. The design checks displayed on the right are now the design checks done for that critical beam for which the highest controlling ratio was reached.
The Percent Comp pull-down control lists the available percentages of composite action for the currently selected design. As you select different percentages of composite action, the total number of shear studs, the design controlling ratio, and the design checks on the right side are updated. The percentage of composite action you select only applies to the currently selected design. The values in the Percent Comp pull-down list change as you select different designs from the list of designs.
When the selected beam is a girder supporting other beams, the Uniform Shear Studs toggle lets you choose whether the shear studs should be listed as a total number uniformly distributed, or as a breakdown across the segments of the girder defined by the beams framing in. Again, the choice here only applies to the selected design.
The Camber clicker allows the camber to be increased or decreased for the currently selected design. The increment is the Camber Increment set in the Composite Design Preferences form. Again, the camber specified this way only applies to the selected design.
Auto Select List pull-down control lets you choose a different auto select list for the beam, or no auto select list at all, in which case the section of the currently selected design will be assigned to the beam. If no auto select list is assigned to the beam, NONE is displayed. When the auto select list is changed, the design results are updated and this may take a while if the beam is part of a large design group.
The Specify Section button displays the Select Sections form. Use the form to select a new section for assignment to the selected beam. The selected section replaces any auto select list.
If the selected beam is part of a group and if that design group was considered in the design of the beam, the Group pull-down lets you remove the beam from that group, or put it back in.
Click the Overwrites button to display the Composite Beam Overwrites {Code} form. Use the form to review and revise design criteria for the selected beam. Any changes made are committed to the model when you click the OK button in that form, even if you later cancel out of the Interactive Composite Beam Design and Review form.

The items on the right side of the form cannot be edited; they display information on the beam and the selected design or allow access to more detailed information.

The Beam and Story display boxes usually show the label associated with the selected beam and the label of the story it is on. However, when the beam selected is part of a group and Show Group Results is toggled on, the Beam and Story display boxes instead show the label associated with the critical beam for which the highest controlling ratio was reached, and the label of the story that critical beam is on.
The Last Analysis display box shows the name of the section that was used for this beam in the last analysis. Thus the beam forces are based on a beam of this section property. For the final design iteration, the Current Design section property and the Last Analysis section property should be the same. If the two differ, you need to re-run the analysis and then use the Composite Beam Design menu > Verify All Members Passed command, and redesign any members that no longer pass.
The Strength Checks displays three columns of numbers. The first column lists the factored values of the shear, positive moment, and negative moment if any, that were considered in the design checks. Unless the beam is shored during construction, the design load combinations must include some with construction loads and the positive moment is checked both at construction time and in service conditions. The second column lists the corresponding allowable maxima for the currently selected design. The third column lists the ratios of the numbers in the first two columns. These ratios all need to be less than 1 (or less than the Stress Ratio Limit set in the Composite Design Preferences form for the design to be acceptable. The stress check yielding the highest ratio is highlighted in bold. If the design is not acceptable due to one or more stress check, those checks are shown in red.
The Constructability and Serviceability Checks likewise displays the details of several types of checks: a shear studs crowding check, the deflection checks for the various load conditions, and one or more vibration checks if a vibration criteria has been specified. Again, the numbers in the first column are the values that were considered in the design checks, the numbers in the second column are the allowable corresponding maxima, and the numbers in the third columns are the ratios of the numbers in the first two. The ratios all need to be less than 1 for the design to be acceptable. The check yielding the highest ratio is highlighted in bold. If the design is not acceptable due to one or more constructability or serviceability check, those checks are shown in red.
The Combos button accesses the Design Load Combinations Selection form. Use that form to make temporary revisions to the design load combinations considered for the composite beam and review the results using the Diagrams or Details buttons. This may be useful, for example, to view the results for one particular load combination. The changes made here to the considered design load combinations are temporary. They are not saved when you exit the Interactive Composite Beam Design and Review form, regardless of whether you click OK or Cancel to exit.
The Diagrams button displays the Design Diagrams at { Beam Number} at {StoryID} form. Use the form to look at the applied loads, shear, moment, and deflection diagrams for the selected beam. If the selected beam is part of a design group and Show Group Results is selected, the critical beam in the group is displayed.
The Details button displays the Report Viewer and a summary of the design data for the currently selected design. The form has buttons to move through the pages of the summary, to Zoom into the individual report pages, print the report, and save it to the Word compatible format.