PLACEMENT-ORIENTED DESIGN AND DELIVERY OF CONCRETE REINFORCEMENT

The use of reinforced concrete in the United States is steadily increa sing, and with it the need for designed and fabricated reinforcing bar s (rebar). Traditionally, the detailing of the rebar is done by the fa bricator, who is required to have the shop drawings approved by the ci vil engineer in charge of the structural design. Subsequently, the reb ar is fabricated and shipped to the site where an independent subcontr actor places the rebar according to the detail design. Research has sh own that the delivery of construction material is strongly related to the productivity of construction processes, such as laying rebar. Howe ver, traditional rebar fabrication and shipment is geared towards mini mizing the set-up time of the rebar bending machine. As a result, reba r is cut, bent, and bundled according to shape and size without consid ering the sequence of placing the bars. This paper presents an alterna tive way to design and deliver concrete reinforcement that is based on computer integration and feature-based design concept. Detailing data generated with CAD software is used to create rebar placement plans, shipping schedules, and assignments of lay-down area on the constructi on site. Based on experiences with the application of the system, step s necessary for its implementation are discussed.