Sustainable Maintenance of Steel Truss Bridges: A Conceptual Framework

Abstract

This paper proposes a conceptual framework for the essential maintenance of truss bridges based on an accurate remaining fatigue life estimation technique. The framework mainly consists of structural appraisal based critical members and connections identification, remaining fatigue lives estimation of critical connections and time dependent member replacement or strengthening scheme. In the stage of critical member identification, detailed structural appraisal has to be conducted giving priority to visual inspection for condition, FE analysis, and material testing, experimental static and dynamic load testing. Accurate fatigue life estimation techniques of both members and connections consist of measured stress histories and recently developed new fatigue models. A verification of the proposed framework is conducted by comparing the predicted replacement scheme with a sequence of experimental failure and fatigue life of selected test specimens. Finally, the proposed framework was applied to a case study railway bridge to obtain time dependent member replacement scheme and obtained results were compared with previous estimations. Hence, validity and merits of the proposed framework were confirmed.