In the United States, a project-delivery revolution that’s been building for years is unfolding. As software continues to “eat the world,” Model Based Design and Construction (MBDC) has been slowly and methodically added to the menu.
MBDC is the use and transfer of digital data and information among design and construction to convey design intent, capture as-constructed data, and provide data for asset management. MBDC, including the use of 3D models as legal contract documents, is being deployed on a variety of bridges under design and construction by state Departments of Transportation across the nation.
How did the industry get to this point, and what’s still needed to facilitate widespread adoption?As most in the industry know, digital design and 3D modeling have been parts of the normal design-to-construction workflow for many years. Unfortunately for the industry’s overall efficiency, the normal workflow also includes 2D drawings, usually shared as PDF files, serving as the legal documents submitted for review, contracting and construction.
The result is the potential for design intent to be lost when converting from 3D models to 2D plan sheets or, more commonly, less design detail being generated in the first place.Both scenarios leave gaps in the overall intent, opening the possibility for requests for information, change orders, schedule delays and possible legal conflicts. It also results in an incomplete as-built model, inhibiting efficient facility management during the life of the asset.
To usher in broad acceptance of BIMs as legal construction documents and as an alternative to 2D PDFs, a standard workflow and data exchange model is needed that satisfies the requirements of designers, reviewers and contractors. a pair of 2013 papers, “Bridge Data File Protocols for Interoperability and Life Cycle Management: Information Delivery Manual for Highway Bridge Interoperable Data Protocols” and “Bridge Data File Protocols for Interoperability and Life Cycle Management: Model View Definitions for Highway Bridge Interoperable Data Protocols,” S.S. Chen et al identified the shortcomings of existing BIM data schemas and workflows for use on bridge projects, and mapped a path forward for using BIM for bridges and structures.