Priority ranking towards condition assessment of existing reinforced concrete bridges

Abstract

Existing old bridges in most countries were designed for less traffic and are inadequate to carry current-day traffic and satisfy the present codal provisions. Even for newer bridges, deterioration caused by unforeseen service conditions and deferred maintenance is causing great concern to bridge engineers. Hence, there is an urgent need for a systematic methodology for priority ranking of the bridges for both their rehabilitation in the future and for the allocation of funding. In this paper, an Analytic Hierarchy Process (AHP), which is an efficient decision making tool for complicated problems with multiple evaluation criteria and uncertainty, has been proposed for the condition ranking of reinforced concrete (RC) bridges. Fuzzy logic is used to handle the subjective judgement, imprecision and intuition involved in a bridge inspector's evaluation report. This methodology would certainly help engineers and bridge management policy makers to overcome the problems related to prioritization and decisions on funding related to the rehabilitation of bridges. The background information, the formulation and the details of the computer program developed in this study for the condition ranking of bridges are presented in this paper. The methodology and its application are demonstrated through a case study.

Keywords:

• Analytic Hierarchy Process
• Decision scale
• Comparison matrix
• Closest Discrete Pair-wise (CDP) matrix
• Real Continuous Pair-wise (RCP) matrix
• Eigenvalue solution
• Fuzzy synthesis
• Condition ranking
• Prioritization

Acknowledgement

This paper is being published with the kind permission of the Director, Structural Engineering Research Centre, Chennai, India.