Reliability assessment, performance prediction and life-cycle management of fatigue sensitive structures based on field test data

In the analysis of structural deterioration processes of steel bridges, fatigue is one of the primary safety concerns. Therefore, fatigue performance assessment and life-cycle prediction have to be used throughout the anticipated service life of fatigue sensitive structures for mitigating fatigue damage and preventing sudden fatigue failure. The preservation of long-term satisfactory structural performance by using optimal maintenance-management interventions under uncertainty is more effectively achieved by the integration of structural health monitoring (SHM) data in the prediction models.;The main goal of this study is to develop efficient probabilistic approaches for the reliability assessment, performance prediction, and life-cycle management of fatigue sensitive bridge and ship structures by incorporating SHM data. In order to achieve this goal, SHM data for existing structures are used in investigating the current practices and methodologies associated with performance assessment and life-cycle maintenance-management of fatigue sensitive structures.;In order to quantify the performance of bridge or ship structures, the time-dependent reliability assessment and lifetime performance prediction for fatigue are investigated. A novel approach for reliability assessment, performance prediction and life-cycle management of fatigue sensitive structures by integrating the SHM data is proposed. Integrating probabilistic lifetime sea loads obtained from model test data into fatigue performance assessment of high-speed ship structures is also proposed. An approach for the reliability-based bridge maintenance interventions by incorporating both crack growth and probability of detection models is developed. Methods for the optimization of life-cycle maintenance of structural systems sensitive to fatigue by considering reliability-based performance measures are developed as well. Finally, an approach for the system-based reliability assessment and prediction of ship structures is presented.;The suitability and applicability of the proposed probability-based approach are illustrated on bridge and ship structures including existing highway bridges, a joint high-speed sealift ship, an aluminum crew boat, and a single hull girder ship. These applications demonstrate that damage identification and remedies for fatigue sensitive structures under uncertainty are more rationally performed by integrating SHM data into the time-dependent reliability assessment, performance prediction, and life-cycle management interventions.