Using the Program

GEOPAK Rebar uses an intuitive interface featuring the usual drop-down menus and toolbars that are becoming the standard. Reinforcement detailing is first drawn in 2D. The level on which an object is drawn tells Rebar what kind of object it is, for example whether it is a footing, abutment, or column, and Rebar then automatically annotates the bars accordingly.

The program is dimension-driven, so a bar type is first picked from the toolbar and placed inside the boundaries of the concrete structure being reinforced. The parameters of the bar are then adjusted using the drop-down menu, and the bar moves automatically to the correct clearance and length. Bars that overlap in a plane perpendicular to the viewing plane can be set to display as being slightly offset in the current view for clarity, although Rebar actually models and dimensions the bars at their true locations.

The files are saved as ordinary .dgn files. A word to the wise: a painful lesson I learned from first-hand experience on the first bridge project is the importance of not editing the .dgn file without first loading Rebar into MicroStation! If you make changes to your design in MicroStation and then attempt to load Rebar afterward, the program will throw error messages at you advising you of discrepancies between its database and the .dgn file. You will then either have to figure out how to make the same changes again in Rebar to reflect your drawing changes, or allow Rebar to undo your work by regenerating the display from its own database!

After developing the design in 2D, the designer has the option of generating a 3D model. This 3D model is automatically extrapolated from the 2D information contained in the section, elevation and plan views, and can be used to check for bar clashes and areas of congestion, which the program automatically detects and highlights. Once the 3D model is created, Rebar automatically keeps it updated each time changes are made to the 2D views. The model can be used to visually inspect the design for bar congestion, as well as produce images and movies useful for design review and construction feasibility assessment.

The parametric features of the program are quite powerful. Quantities are calculated and custom bar schedules kept current, dimensions are placed automatically, bars are drawn completely to scale and modeled accurately (bar thickness included), various views are maintained, annotations updated, and nominal bar sizes set to accommodate the English or metric units used by each sheet.