Variable Depth Slab Bridge Design Software – History

V Slab Development History

This section provides documentation of the history and development of V Slab software.  

Build 2021-3 was released on April 28, 2021 to address detailed special vehicle reactions on the report printout.

Build 2021-2 was released on March 6, 2021 to correct a calculation problem related to the bottom area of steel in the exterior strip.

Work began on V Slab, version 5 in the summer of 2020 after the release of the 9th Edition of the AASHTO LRFD Bridge Design Specification.  Reinforcing development and splice tables were added, and new display features were incorporated into the visual reinforcing layout editor.  V Slab version 5 was release in February 2021.

In May of 2019 and again in July of 2019 new build versions were released.  These addressed some report issues and other minor changes based on user input.

V Slab, v4.0: Various improvements were implemented and the code check was updated to the AASHTO LRFD Bridge Design Specification, 8th Edition. Version 4.0 was release in March 2018.

Code verification was completed with new releases. Programming efforts to make improvements to reports and default values began in 2017.

V Slab, v3.0.1: A few display and printing issues were fixed. An error was corrected related to printing special vehicles load ratings without including them in the design envelope.  Version 3.0.1 was release in March 2011.

V Slab, v3.0: Version 3.0 involved major improvements. The user interface was entirely replaced with a more conventional toolbar menu system. Special loading options were added and design envelope selections were provided. Load rating using LRFR and the AASHTO Manual for Bridge Evaluation were implemented including special vehicles and fatigue. A graphical reinforcing bar layout screen for interior and exterior strips was implemented. Bar splice options were provided. The bar layout system also allows bar corrosion to be entered for load rating. Version 3.0 was release in February 2011.

V Slab, v2.0.1: A few entry issues were reported and fixed. An error was corrected related to printing a shear table in the report for a simple span condition. The program was reviewed for compliance with the LRFD Code, 5th Edition. V Slab, v2.0.1 was release in July 2010.

V Slab, v2.0: To accomodate variable depth slabs, the LRFD Slab Bridge program had to be almost entirely rewritten. The internal program modifications were significant enough to warrant a new name. However since the new program looks and acts similar to the original program, the version number was incremented from the previous one for continuity. V Slab, v2.0 was release in January 2010.

LRFD Slab Bridge, v1.2: Several modifications were completed through the testing process. Some of these changes required new program features and different save files, resulting in the release of a new version. Minor changes were implemented after the this release so a new build was issued as Version 1.2.1.

LRFD Slab Bridge, v1.1: Near the end of 2008, bar cutoffs and substructure design was implemented. By this time, the software had developed into a commercial application. Work was completed on the setup program, licensing lock and printing/saving features, and version 1.1 was released for beta testing in early 2009.

LRFD Slab Bridge, v1.0: Work began on the LRFD Slab Bridge program in about 2005. The graphics interface and live load model were developed first. In 2007, version 1.0 was completed for testing purposes only. The program completed live load analysis and slab reinforcing layout without bar cutoffs or substructure design.

The original slab bridge design program “SLABBR.EXE” was developed in 1994 for a DOS based operating system. This program followed the provisions of the AASHTO Standard Specification for Highway Bridges. This program was updated several times to add features until about 2003 when it was determined a new version, using the LRFD Code, was needed.