BAP Development

Following is a chronological listing of the development of BAP:


12/3/2013 BAP 3.4.0002 is released. This version of the program corrects several metric unit results displays, adds an option to show or hide the "Calculate Stress" options, and corrects an error when loading the "Get Truck Series" and "Get Truck" options.
3/17/2013 BAP 3.4.0001 is released. This version of the programs adds the following functionality:
  • A Section List allows standard sections to be saved for quick and accurate input in the sections tab. The section list includes section description, moment of inertia, CTop, CBot and section weight. The section list is automatically saved for use in new projects. In the Input Window's Section's tab, when the section description is selected, a drop down list shows all of the available sections included in the sections list. When a section is chosen from the list, it populates the Moment of Inertia, CTop, CBot, and Section Weight fields.
  • CTop and CBot are added to the Sections tab. CTop is the distance from the section's neutral axis to the extreme fiber in bending at the top of the beam. CBot is the distance from the section's neutral axis to the extreme fiber in bending at the bottom of the beam.
  • If values are provided for CTop and CBot, BAP calculates the stress at the top of beam and bottom of beam at the selected increments. These values are shown in the Results window, moment tab, the printer output, and the Excel export file.
  • In the Results Window, Shear, Moment, Deflection, and Rotaion tabs, you can now enter a distance along the beam and the corresponding values will be calculated at that point.
  • In the Results Window, Shear, Moment, Deflection, and Rotation tabs, the local maximum and minimum values are highlighted yellow for moment, stress at top of beam, and stress at bottom of beam.
  • The Reults Window has a new menu item called "Allowable Stress," which provides the option of showing a red "Allowable Stress" line in the "Stress at Top of Beam" and "Stress at Bottom of Beam" diagrams for allowable tension stress and compressive stress.
9/30/2012 Error notification and fix. When using metric units and kilonewtons, the values for reactions, shear, and moment were off by one decimal point in the .csv file created by the "Export Results" to Excel. This error has been fixed in BAP Version 3.3.0002. This version of teh program also updates all contact emails to Juntunen Bridge Systems to
3/15/08 BAP 3.3.0001 is  released. This version of the program allows load input as pounds or kips for english units, and Newtons or Kilonewtons for metric units.


10/23/05 Error notification and fix. When using metric units, the values for deflection and rotation were off by two decimal points; i.e. - a value of 5 mm deflection would be shown in the program output as 500 mm. Also, when using metric units, the column header, "Distance to Section" shown in the input verification table for sections listed the distance as "feet." Both errors have been fixed in BAP Version 3.2.0001.


2/14/05 BAP 3.2 is released. BAP Version 3.2 offers the following enhancements: An option to solve for a series of truck loads. Up to 30 different trucks can be run over the beam. BAP will solve for lower bound and upper bound values for reactions, shear, moment, deflection, and rotation, and tell which truck produces the controlling value. The truck series can be saved for use in future problems. A new matrix solver for faster and improved performance. Results can be saved in a coma-delineated file, which can be called into a spread sheet program such as Microsoft Excel.


12/16/03 The drawing routines for shear, moment and deflection are modified to speed up the program when running truck loads. The diagrams no longer saves previous shear, moment, and deflection diagrams when the truck is repositioned (This was causing the program to run slowly). Users of truck loads are recommended to download BAP Version 3.01.0002 which is available on the BAP update page.


7/26/01 Error notification. When quotation marks " are used in data input (example - descriptions of point loads or distributed loads, or problem description), when a file is saved and then opened, the data will be corrupted. This happens because Quotation marks " are used by BAP to indicate string variables in the data file. This problem will be corrected in the next version of BAP. Meanwhile, to avoid this problem, please do not use quotation marks " in your data input.


2/25/01 Error notification and fix. When a beam has large section changes occurring to the right of a hinge, erroneous results can occur for deflection and rotation. This problem was fixed by modifying the 1st. and 2nd. integration of the beam equation as shown in the updated help file. This problem is corrected in BAP Version 3.01.0001, which can be downloaded from this website. All registered users of BAP3.0 are encouraged to download the latest version of the software. The latest version of the software makes greater use of double precision variables to give more accurate results for reactions, shear, moment, deflection, and rotation. Rules for placement of hinges are also provided (See the help file for further information). Go to Update BAP 3.0


2/25/01 When running problems with a moving load, multiple spans, and many section changes, and you chose a small increment to show results, and you show a small increment to move the truck load, the program may take a very long time to run. For large problems like this, use larger increments to move the truck and show results. Typically 10 increments per span will provide adequate results, and the program will run fairly quickly. If you picked a very small increment and the program is taking forever, you can halt execution by hitting ctrl-alt-delete, and end the (BAP3) task. This will exit the program altogether.


2/6/01 BAP3.0 is updated. The printer output indicates that "Section Weight" is not included in the analysis and the Section Weight column is not shown when the "Include Weight" box is not checked in the "Sections" tab.


1/9/01 BAP3.0 is updated. The program was changed so the user selects the increment at which the shear, moment, and deflection is calculated when the "Run" button is clicked.


1/7/01 BAP3.0 is released.


6/25/00 BAP3.0 Beta Version is released for testing.


11/8/99 Minor change made to the bap2.exe file; In the "About Window" the bap2.exe file creation date shown was changed from 5/1/99 to 11/8/99. The update for this file is available to registered users of BAP2 from this website by going to BAP2 Update.


11/5/99 Error notification and fix. When running truck loads, the results for the "Lower Bound Rotation (Deg.)" and "Upper Bound Rotation (Deg.)" are correct on the first run of the data. But, if the data is changed and subsequent runs are made without exiting the program, the results for "Lower Bound Rotation (Deg.)" and "Upper Bound Rotation (Deg.)" may not be correct; i.e. - If the new results are less than the original values from the first run, the results from the first run will continue to be shown. This error has been corrected in the bap2.exe file dated 11/5/99.


5/6/99 Beta testing is complete on BAP2.1, and this version of the software was also renamed (back to) BAP2.0 with the compile date shown in the "About Box" of the software to indicate the version of the software that is being used. The beta testing showed that erroneous results can occur for rotation (slope) when a distributed load was used along with changes in cross section. This has been corrected. Other updates are; The file name was added to the Title Bar for both the Input window and the Results window. Minor corrections were made to the print file, and the registration number is no longer shown in the "About BAP2.0" window. The BAP2.0 version, compile date
5/1/99 was made available at this web site. If you have downloaded the version BAP2.1 Beta, you are encouraged to delete that version from your computer and download the latest final version of the software.


4/15/99 BAP2.1 Beta is now available from this website. This version of the program can calculate the rotation (slope) at increments across the beam.


2/28/99 - Note. All distances, except moving loads, are input as distance from the left end of the beam. Moving load distances are referenced to Moving Load Number 1.


2/28/99 - Note. Always remember to watch your units! For example, when inputting a moving load, remember to convert the load to load per beam before inputting the magnitudes; i.e. - convert from load per axle or load per wheel to load per beam.


2/28/99 - Error notification. The BAP2.0 help file, under the topic, Moving Loads, second paragraph, reads "Magnitude of each moving load is input as pounds or

'meters'... "Meters", should read "Newtons."

Juntunen Bridge Systems
6028 Bradford Lane
Lansing MI 48917
Phone: (517) 512-3120
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