Time-dependent reliability assessment of existing concrete bridges including non-stationary vehicle load and resistance processes

• Published in: Engineering structures Vol. 197; p. 109426
• Main Authors: Yuan, Yangguang, Han, Wanshui, Li, Guangling, Xie, Qing, Guo, Qi
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.10.2019; Elsevier BV
• Subjects: Bridge loads; Bridge maintenance; Component reliability; Concrete; Concrete bridges; Deterioration; Existing concrete bridges; Extreme values; Gamma process; Generalised extreme value distribution; Inspection; Load resistance; Non-stationary properties; Reliability analysis; Target reliability index; Time dependence; Time-dependent reliability assessment; Time-dependent reliability assessment; Existing concrete bridges; Gamma process; Non-stationary properties; Target reliability index; Generalised extreme value distribution
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2019.109426

•The non-stationary properties of vehicle load process and resistance deterioration process are considered simultaneously to propose a time-dependent reliability assessment procedure.•Specifically, the dynamic generalized extreme value distributions and the Monte Carlo simulation are combined to realize the extreme value modeling of non-stationary vehicle load process, in which the actual properties of vehicle load are included.•The Gamma process is employed in the modeling of non-stationary resistance deterioration mode, besides this, an updating procedure is introduced to reduce the discrepancy between the prior model and the actual deterioration characteristics.•In the last, the hazard-function-based time-dependent reliability analysis method is developed to propose the assessment procedure. It is well known that existing concrete bridges are time-varying working systems, and the corresponding maintenance strategy should be planned according to the time-varying service performance. In this work, a time-dependent reliability assessment procedure is proposed while including the non-stationarities of the vehicle load process and resistance deterioration process simultaneously, which are the two factors that significantly influence the time-varying service performance of a bridge structure. To achieve this goal, the following key tasks are conducted in sequence: (a) extreme value modelling of non-stationary vehicle load process; (b) model establishment and updating of non-stationary resistance deterioration process; (c) determination of target reliability index of a concrete bridge component in the operation stage; (d) performing time-dependent reliability analysis while considering the non-stationary properties. In addition, a case study is conducted to illustrate the application of the proposed procedure by considering an existing concrete bridge as an example. It is found that the proposed time-dependent reliability assessment procedure is feasible, and some critical information on the time-varying service performance of the existing concrete bridge component can be obtained, which can be further referenced in the planning of the structural inspection, management and maintenance, etc.