C-AHP rating system for routine general inspection of long-span suspension bridges

Abstract

Different from the condition rating system for bridges, the criticality and vulnerability rating system for long-span suspension bridges is used to determine the time intervals for routine general inspection of key structural components of the bridge. In consideration of uncertainties involved in the current rating system for long-span suspension bridges, this study presents a cloud-based analytic hierarchical process (C-AHP) rating system to determine inspection intervals. A three-level hierarchical structure is first introduced in terms of criticality and vulnerability, and the relative weights for the hierarchical structure are determined by AHP. The Gaussian cloud model is then introduced to the AHP rating system to form a C-AHP rating system for long-span suspension bridges. Finally, the feasibility and effectiveness of the proposed C-AHP rating system are calibrated by using the Tsing Ma Bridge in Hong Kong as a case study. The case study results show that the proposed C-AHP rating system could take into consideration not only fuzziness but also randomness in the AHP rating system and provide stricter time intervals than the F-AHP rating system for routine general inspection of long-span suspension bridges.