Abstract

This paper provides an overview of the reliability-centered maintenance (RCM) engineering process. RCM is a unique tool used by reliability, safety, and/or maintenance engineers for developing optimum maintenance plans which define requirements and tasks to be performed in achieving, restoring, or maintaining the operational capability of a system or equipment. Implementing the RCM process requires the application of a decision logic that enables systematic analysis of failure mode, rate, and criticality data to determine the most effective maintenance requirements for maintenance-important items. It is through this process that the scheduled maintenance burden and support costs are reduced while sustaining the necessary readiness state. The RCM process is designed to focus engineering attention to the part level in a formal and disciplined manner leading logically to the formulation of a maintenance strategy and plan. RCM benefits include: *The development of high quality maintenance plans in less time and at lower cost. *The availability of a maintenace history for each system; one is able to correlate this experience with specific parts and their failure modes and criticalities. *The assurance that all maintenance-important parts and their failure modes and criticality are considered in the development of maintenance requirements. *The increased probability that the level and content of the maintenance requirement is optimally specified. *The basis for routine, on-line information exchange among the engineering staff and management even in a widely dispersed organization. Document type: Report

Abstract

International audience; In recent years, a great deal of attention has been paid to the analysis of failure modes occurring in railway infrastructure assets, e.g. bridges, rail tracks, sleepers, etc. However, there have been few attempts by researchers to develop failure criticality assessment models for railway rolling stock. A rolling stock failure may be very costly in terms of monetary loss and/or passenger inconvenience. It may also cause delays to train services or even result in catastrophic derailment accidents. In this paper, a failure mode, effects and criticality analysis approach is presented to identify, analyse and evaluate the causes and consequences of rolling stock failures. The most critical failure modes with respect to both reliability and economics are identified and potential protective measures are then proposed to prevent their recurrence. For the purpose of illustrating the proposed approach, the model is applied to a rolling stock passenger door system. The data required for the study are collected from both the literature and the maintenance information system available in a Scottish train operating company. The results of this study can be used to plan a cost-effective preventive maintenance programme for different components of rolling stock.

Abstract

Composites made of fibers embedded in organic or inorganic matrices are efficient systems for reinforcing historical masonry structures to provide strength and ductility with a negligible mass increment. As it is well known, the structural performance of the composites mainly relies on their adhesion to the substrate. There are different methods to test the adhesion of the composite to the substrate: in laboratory direct shear test is the most commonly employed, while on-site the bond between the reinforcement and the substrate is checked by the pull-off test. In this paper, the adhesion of different composites to the same substrate made of fired-clay bricks is investigated by both the shear test and the pull-off test to qualitatively assess the difference in the two methods. Additionally, to investigate whether the bond is affected by the presence of water in the pores, half of the specimens were tested in water saturated conditions. Three different types of matrix (based on epoxy resin, natural hydraulic lime and Portland cement) were used for the composite matrix, without changing the geometry, the type of masonry substrate and the fibers (galvanized steel cords).