Reliability assessment and maintenance optimization of a load-sharing system considering dependent failure rates and component heterogeneity

TY - JOUR

T1 - Reliability assessment and maintenance optimization of a load-sharing system considering dependent failure rates and component heterogeneity

AU - Zhang, Nan

AU - Yi, Xiangjian

AU - Ma, Yiqi

AU - Cai, Kaiquan

N1 - Publisher Copyright: © 2025 Elsevier Ltd.

PY - 2026/5

Y1 - 2026/5

N2 - In this paper, we consider the reliability and maintenance assessment of a load-sharing system. The system consists of multiple heterogeneous components. We assume that an increase in load leads to the increase of the failure rate of each working component. Two system configurations are studied: the K -out-of- N systems and systems with critical components. The system reliability measures such as the reliability function, the conditional reliability function and the remaining useful lifetime of systems are derived. By assuming that the system failures are hidden, a periodical inspection is proposed, upon which, the decision-maker has the flexibility to do nothing and wait for the next inspection epoch, or to replace the failed components. The expected discounted maintenance cost in the long-time horizon is taken as the objective function. The problem is casted into the Markov decision process. We utilize the value iteration algorithm to solve the optimization problem. A numerical example is presented to show the applicability of the proposed model. The impact of the load-sharing has been comprehensively investigated through sensitivity analysis. It is seen that load-sharing shows significant impact on system reliability and maintenance costs. It can provide theoretical reference to the decision-maker in developing maintenance policies and controlling maintenance budget.

AB - In this paper, we consider the reliability and maintenance assessment of a load-sharing system. The system consists of multiple heterogeneous components. We assume that an increase in load leads to the increase of the failure rate of each working component. Two system configurations are studied: the K -out-of- N systems and systems with critical components. The system reliability measures such as the reliability function, the conditional reliability function and the remaining useful lifetime of systems are derived. By assuming that the system failures are hidden, a periodical inspection is proposed, upon which, the decision-maker has the flexibility to do nothing and wait for the next inspection epoch, or to replace the failed components. The expected discounted maintenance cost in the long-time horizon is taken as the objective function. The problem is casted into the Markov decision process. We utilize the value iteration algorithm to solve the optimization problem. A numerical example is presented to show the applicability of the proposed model. The impact of the load-sharing has been comprehensively investigated through sensitivity analysis. It is seen that load-sharing shows significant impact on system reliability and maintenance costs. It can provide theoretical reference to the decision-maker in developing maintenance policies and controlling maintenance budget.

KW - Failure dependence

KW - Hidden failures

KW - K-out-of-N

KW - Load sharing

KW - Markov decision process

UR - https://www.scopus.com/pages/publications/105024981717

U2 - 10.1016/j.ress.2025.112072

DO - 10.1016/j.ress.2025.112072

M3 - Article

AN - SCOPUS:105024981717

SN - 0951-8320

VL - 269

JO - Reliability Engineering and System Safety

JF - Reliability Engineering and System Safety

M1 - 112072

ER -