Content area
Abstract
The two main goals of this research were: (1) to develop and test a CAD-integrated intelligent process planning system for the placement of reinforcing bars (rebar), and (2) measure the effects of placement-oriented bundling, tagging, delivery and staging on the crew-level productivity. For the first goal an extended input/output (I/O) process model has been developed to better represent the dynamic nature of construction. This modified I/O model demonstrated the need for utilizing process-oriented planning concept for the placement of rebar in concrete construction. Feature based frameworks for design and planning were established to allow the use of artificial intelligence (AI) in the development of a CAD-integrated process planning system. The thesis also includes a discussion of the system architecture of a computerized prototype. The CAD-Integrated Rebar Placement Planning System (CRPP) is implemented on a PC-486 computer using LEVEL5 OBJECT, AutoCAD and dBASE III PLUS.
The second goal of this research is based on extensive comparative field experiments in the construction of a six-story governmental office building project in Chapel Hill, North Carolina. Three different methods of observation were utilized to collect data of the same rebar crew being provided with rebar that were bundled, tagged, delivered and staged (a) in a traditional manner, and (b) based on the placement sequence.
The overall outcome of this comprehensive research project indicates that process-oriented planning, computerized and CAD-integrated, can yield drastic improvements in the crew-level productivity. This study showed that many planning tasks can be automated. Furthermore, such automation in planning, when used in an integrated fashion that also includes material suppliers, etc., may be a key to unlocking the potentials for streamlining construction practices through the use of multi-level planning models.