Application of robotics in bridge deck fabrication

Application of robotics in welding orthotropic steel decks for bridges is investigated. It is found that by using robot welders, savings of about 5.6% can be realized in the fabrication cost of the steel decks. Deterioration of the bridges' concrete decks at alarming rates has bridge engineers looking at alternative systems. Orthotropic steel decks are particularly attractive because they last longer than concrete, reduce the bridge’s dead load and can be replaced without major disruption of traffic. Traditional methods of steel deck fabrication are costly and labor intensive. Based upon the findings of the research described in this paper, if robotics technology is used in steel deck fabrication, the required man-hours and the fabrication costs may be reduced. This would reduce the initial cost of steel decks making them competitive with the cost of concrete decks. Considering life cycle analysis, orthotropic steel decks appear to be even more competitive with the concrete decks. In this investigation, a typical orthotropic deck module was designed using approximate methods. Several steel fabricators were contacted and price quotations for fabricating this module were obtained. A model of a robotics system for welding of this deck module was conceived, the robot’s specifications prepared and the cost of the system estimated. A comparison of the cost of the conventional and robotic fabrication and analysis of results are presented.