Project Tab
The Project Tab Screen is the first screen that you encounter in Precast/Prestressed Girder. It contains specific information related to the project, design code specification, units' selection, span type, State Setting and an option for Flared Girder.If you return to the Project tab at any time to change units, each screen instantaneously converts its values, thereby updating the units to the new selection .
The Span Type offers multiple choices to select from: Simple Span, Multi Span (continuous) , Multi Span (non-continuous), and Multi-Span (Mixed). The Simple Span option allows you to specify information for only one span at a time. The Multi Span (non continuous) option allows you to enter a series of simple spans, and treats all superimposed dead and live loads as acting on the Simple Span model only. The Multi Span (continuous) option should only be selected if the live loads and dead load on composite are to be treated as acting on the continuous spans, and you would like the program to design the deck reinforcement in the negative moment zone.
The multi-span (Mixed) allows you to model and analyze multiple units of superstructure in a single LEAP Bridge concrete file.
The State Setting option represents a new direction for Precast/Prestressed Girder where specific state practices are being incorporated into Precast/Prestressed Girder for use by engineers in that particular state. Currently the following states, including California, Florida, and Pennsylvania are supported. When this option is selected, the program preselects certain user interface options within Precast/Prestressed Girder, helping the user through the process of analysis of the bridge according to Florida's/California's specific design guidelines. This setting is useful primarily when starting data entry for a new data file, and is not recommended for data files previously created or where different options than the state specific criteria need to be applied (for example, using standard specifications (LFD) with Florida's specific state setting). Also note that this state specification option is not a comprehensive check for all the state specific design requirements for the selected state. More state specific setting will be added in future version of Precast/Prestressed Girder, making the use of Precast/Prestressed Girder even more efficient in different parts of the United States.
Selecting the option for Flared Girder triggers a different user interface on the Geometry tab allowing the user to primarily model flared/splayed girder information, and bridges with varying supports skews. A user can model advanced geometric conditions such as alignment information (including curves), different length of girders in the same span, variable spacing of girders at start and end of span, varying deck widths and abutment pier properties. Please refer to the Flared Girder Geometry Appendix for complete details on this particular feature.
Precast/Prestressed Girder uses two levels for the input and design process, as follows:
Level 1 - Project Level
All the information provided in the Project, Geometry, Materials, Loads, Analysis, Beam and Deck tab screens applies to all the beams in the bridge under design
Level 2 - Beam Level
Some of the parameters defined in Level 1 can be modified with respect to the individual beams in the Beam tab screen. For example, if all beams were defined using 1/2-270K-LL draped strands; the user may modify the beam level so that the exterior beam uses 9/16-270K-LL straight strands. For more information, please refer to the Beam Tab topic.
If you switch between them after completing a beam design, you will need to re-select the live load information and rerun the analysis. This is necessary due to the fundamental difference in classification and application of loads between the two design codes. However, any of the completed beam design parameters (i.e., strand pattern, etc.) are not altered.