摘要: |
Background: At the Center for Quality Engineering and Failure Prevention at Northwestern, we have been developing intelligent SHM systems for aircraft and marine structure applications for the past two decades. ITI has been a leader in developing and implementing technological solutions to civil infrastructure maintenance problems. In September 2007, CQE initiated a new NSF-funded five-year effort to establish a network of centers program called Partnerships for International Research and Education: Intelligent Structural Health Management (PIRE-ISHM) of Safety-Critical Aerospace, Mechanical and Civil Structures. The effort on the civil infrastructure side is in conjunction with ITI support. As described in the NSF PIRE-ISHM proposal document, we envisage collaborative activities with ITI in research, education and outreach. Research Theme: Whatever the actual causes of catastrophic failures such as the I35W Bridge in Minneapolis, it is clear that an aggressive Structural Health Management (SHM) approach including schedule-based off-line inspection and on demand on-line inspection is necessary to prevent such disasters. In schedule-based off-line inspection (as currently practiced), diagnostic equipment and sensors are temporarily placed on the bridge at prescribed intervals for scheduled measurements. On-demand (or continuous) on-line inspection, on the other hand, is carried out with permanently installed sensors for what is known as structural health monitoring. We propose to consider both schedule-based inspection and structural health monitoring. These techniques have certain equipment features in common, but there are also significant differences. At the present time, the experience that has been gained with schedule-based inspection is considered to provide major advantages, but the potential economic and safety benefits of structural health monitoring are potentially so significant that future structures are likely to include SHM as part of a robust structural health management program. It is noteworthy that the need for an active approach to structural health management has been recognized by the Transportation Research Board in a document entitled Research Needs Statement [1]. The specific research goals that the proposed SHM program addresses include Safety (USDOT), Infrastructure Renewal especially safety assurance of highway structures (NSSTR goal), and Advanced Transportation Research (FTAR goal). RESEARCH THEME: Whatever the actual causes of catastrophic failures such as the I35W Bridge in Minneapolis, it is clear that an aggressive Structural Health Management (SHM) approach including schedule-based off-line inspection and on demand on-line inspection is necessary to prevent such disasters. In schedule-based off-line inspection (as currently practiced), diagnostic equipment and sensors are temporarily placed on the bridge at prescribed intervals for scheduled measurements. On-demand (or continuous) on-line inspection, on the other hand, is carried out with permanently installed sensors for what is known as structural health monitoring. We propose to consider both schedule-based inspection and structural health monitoring. These teqchniques have certain equipment features in common, but there are also significant differences. At the present time, the eperience that has been gained with schedule-based inspection is considered to provide major advantages, but the potential economic and safety benefits of structural health monitoring are potentially so significant that future stuctures are likely to include SHM as part of a robust structural health management program. It is noteworthy that the need for an active approach to structural health management has been recognized by the Transportation Research Board in a document entitled Research Needs Statement. The specific research goals that the proposed SHM program addresses include Safety (USDOT), Infrastructure Renewal especialy safety assurance of highway structures (NSSTR goal) and Advanced Transportation Research (FTAR goal). |