An object-oriented project model for integrating building design, construction scheduling, and cost estimating for mid-rise construction

In this study a project model for integrating building design, construction scheduling, and cost estimating at the preliminary design stage was developed and analyzed. The project model is developed in an object-oriented environment. The project model accepts a set of preliminary design parameters and generates an integrated schedule and cost estimate. The project model allows for interactive and iterative changes of design and construction plans, and allows for the evaluation of the impacts on the schedule and on the cost estimate due to these changes. The project model consists of an object-oriented system environment and a set of interactive and iterative processes. Seven major elements are designed in the object-oriented system environment: (1) Object Library; (2) Process Modules; (3) Blackboard; (4) Interactive Editors; (5) Project Scenario Files; (6) Historical Project Files; and (7) System Controller. The processes are (a) Design Initialization; (b) Initial Scheduling; (c) Detailed Scheduling; and (d) Cost Aggregation. The scope of this research is limited to mid-rise building construction. A prototype system of the project model was implemented on a personal computer using a windows-based, object-oriented programming environment, KAPPA-PC$\sp{\rm TM}$. The prototype system incorporates several external programs for various scheduling and financial analysis purposes.