Delivering Value Through the Use of Three Dimensional Computer Modeling
Corresponding Author: Zabelle, Todd R.
Author(s): Zabelle, T.R.
Organisation(s): Pacific Contracting / Lean Construction Institute, San Francisco, California (USA)
Over the past several years the use of three-dimensional computer modeling amongst specialty contractors has been on a steady increase. This increase however is doing little to deliver value to the project owner. As a matter of fact it may be doing the opposite. 

Current practice consists of using three dimensional computer modeling for coordination of construction documents, detailed planning of construction operations and as programming for numeric manufacturing equipment. Upon receiving contract documents such as drawings and specifications prepared by design firms specialty contractors digitally construct a mock-up of the project. As the mock-up is being developed it is checked against shop drawings and detailed engineering from other trade contractors in an effort to identify and resolve conflicts. Intersections, connections, transitions and terminations of systems and components are analyzed in the greatest detail, as they are the most common areas of conflict. Once a conflict is identified it is digitally represented and the effected parties resolve the issue. Upon resolution of the conflicts specialty contractors are then able to use the database behind the model to drive numeric fabrication equipment and prepare a consolidated bill of materials. 

Best Practice is based on true concurrent engineering throughout the project development process. All participants in the project share the same model and provide design information based on optimization of the total project rather than an individual component or system. The model supports lean production strategies such as value generation; pull or demand based release of work and continuous improvement. New technologies such as computer aided process engineering (CAPE) is deployed to visually model production processes. At the conclusion of the construction portion of the project an interactive digital model is delivered to the client to support future alterations and ongoing operations.

Through project specific case studies this paper presents how three dimensional computer modeling is being used in localized areas of AEC projects today and how it can be leveraged to deliver real value in the future.