IMPROVING DESIGN AND FABRICATION OF BRIDGES USING KNOWLEDGE-BASE

Because the cost of steel bridges in Japan is generally estimated using the price per unit weight, bridge designers and fabricators are required to decrease the steel weight of the bridge. This results in increasing the number of cross-section variations and the number of weld lines. However, because of the shortage of technicians and increase in labor cost, it is becoming necessary to consider the possibilities of simplifying and accelerating the fabrication process to get a more rational and a near optimal design. Knowledge-based systems, when combined with actual design data of available bridges, can support the decision-making process for improving both design and fabrication. This paper discusses the creation of a knowledge base that includes data on previously designed plate-girder bridges, and its application in considering the effects of simplifying the design on the cost of the bridge. First, the steps used in the creation and processing of the knowledge base are explained. Then, the knowledge base is used to investigate several design alternatives by selecting and redesigning some bridges. Several suggestions for a more rational design are given, based on previous design information.