Total Bridge Analysis and Design without Geometric Design (Slab or Box Girder)

If your goal is to define, analyze and design a slab or box girder b ridge superstructure and substructure, but the geometric design is not a concern, we recommend you only use CIP RC/PT Girder and Substructure.

In this case, the bridge definition will be first done by using CIP RC/PT Girder to define the number of spans, superstructure layout and cross section definition and variation, and pier/column layout and properties. Once the CIP RC/PT Girder analysis and design process is concluded, you can closeCIP RC/PT Girder and at the prompt, if you wish to create a LEAP Bridge Concrete model, you need to answer Yes. This will create a database file for the bridge, and a 3-D model of the bridge, including its superstructure and piers. A default roadway will be generated with a flat surface, width equal to bridge width at its beginning, and constant elevation of 100ft.

To continue with the pier design, you now can move to the Substructure tab, select one of the piers, and run Substructure. The pier definition provided in CIP RC/PT Girder will be automatically transferred into Substructure. THis data may not be entirely complete and depending on the situation, some data may need to be provided before a pier analysis can be done. For example, Substructure requires bearing locations to be defined for loads, and at this time this information is not automatically created by CIP RC/PT Girder. Alternatively, an existing Substructure native file can be opened as a starting point. After analyzing or designing the pier, when closing Substructure, you should answer Yes when prompted to update the LEAP Bridge Concrete data set. This will update the LEAP Bridge Concrete database with the pier information, the 3-D bridge description is updated, and the roadway elevation is adjusted to match the pier elevation defined in Substructure. If the selected pier is the first or last pier in the bridge, then the elevation of the adjacent abutment is also adjusted to match the pier elevation.

You can now continue to refine or revise the superstructure or pier design by moving back and forth to CIP RC/PT Girder and Substructure, and modify the data as needed to complete the bridge. To update the LEAP Bridge Concrete database and ensure exchange of data between the components each time you close either CIP RC/PT Girderor Substructure, you need to answer Yes to updating the LEAP Bridge Concrete database. You will also be asked if you want to create the reports. If you answer Yes, then a complete set of reports are generated (not printed) and may be accessed later from within LEAP Bridge Concrete’s Report tab without having to run CIP RC/PT Girder or Substructure. This option also allows another user of LEAP Bridge Concrete to access the results without having to access the components. However, since at this time some aspects of pier geometry are defined differently in CIP RC/PT Girder and Substructure, the data may need to be revised by Substructure. These cases include the following:

CIP RC/PT Girder can define a pier as integral or drop-cap.Substructure treats integral piers similar to drop cap piers for analysis purposes, therefore, the dimensions of the cap must be defined in Substructure, and bearings shall be added by the user.
CIP RC/PT Girder has a column type of General which is defined by properties only, and no shape or dimension. Substructure will convert this column to a 12 round column as a starting point and the user needs to revise it to the desired shape and size.
CIP RC/PT Girder can have a round column with variable section. InSubstructure, round columns cannot have variable section, and therefore the column size on top will be used for the entire length of the column.
CIP RC/PT Girder can mix column types in one pier (e.g., some rectangular and some round). Substructure will change all columns to the same shape as the first column.
CIP RC/PT Girder can have section variation in the superstructure. Substructure uses one set of values for each span, and will select a section from CIP RC/PT Girder as the property set for each span. The user will need to review this information and adjust the values.