Integrated CAD/KBS approach for automating preconstruction activities

Preconstruction activities include design analysis, cost estimating, and value engineering. They are performed to provide clients with the data to make intelligent and informed decisions about constructing their facilities. Cost plays an important part in preconstruction activities; owners want to know accurate construction costs up front to determine if they meet their budget. Various design alternatives need to be considered and compared with respect to cost, performance, and reliability and the best one selected to achieve the ultimate goal of the project. However, often because of the time restraints of preconstruction activities, the number of design alternatives considered is limited. The lack of time is one reason unnecessary cost gets into the design. The effectiveness of preconstruction activities can be improved by expediting the generation of design alternatives and improving the accuracy of their cost estimates. This can be achieved through the integration of knowledge-based systems and computer-aided design systems. This paper discusses such an integration and describes an application developed for the preconstruction analysis of mezzanine structures. Preconstruction analysis of mezzanine is an integrated knowledge-based computer-aided design system that captures structural design knowledge and cost information and enables sales personnel, without engineering background, to produce accurate preliminary designs, realistic price quotations, and detailed layout drawings.