Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The railway transportation system is fundamental in sustaining the economic activities of a country, by providing a safe, reliable and relatively affordable means of transporting people and goods; hence, the need to ensure its ongoing reliability is of paramount importance. The principle and applications of rail reliability have been reviewed, and reliability improvement in rail infrastructure has been investigated using failure mode and effect analysis (FMEA). Reliability improvement is a continuous process that is geared to meeting dynamic changes in operation and stakeholders’ expectations. Recently, growth has occurred in the amount of rail transport traffic utilisation undertaken, together with the degradation of the infrastructure involved. Such deterioration has amplified the operating risks, leading to an inadequacy in rail track maintenance and inspection that should have kept abreast with the changes. The result has been increased rail failures, and subsequent derailments. A case study of the Passenger Rail Agency of South Africa (PRASA) Metrorail maintenance policy was reviewed to evaluate its maintenance strategy and identifying the potential critical failure modes, so as to be able to recommend improvement of its reliability, and, thus, its availability. On the basis of the case study of PRASA Metrorail maintenance strategy and its performance, it is recommended that PRASA Metrorail change its maintenance policy through employing a cluster maintenance strategy for each depot. / AFRIKAANSE OPSOMMING: Die spoorwegvervoerstelsel is fundamenteel om die ekonomiese bedrywighede van ’n land te ondersteun deur die voorsiening van ’n veilige, betroubare en betreklik bekostigbare manier om mense en goedere te vervoer. Dus is dit van die allergrootste belang om die voortgesette betroubaarheid daarvan te verseker. Die beginsels en toepassings van spoorbetroubaarheid is hersien en die betroubaarheidsverbetering van spoorinfrastruktuur met behulp van foutmodus-eneffekontleding (“FMEA”) ondersoek. Betroubaarheidsverbetering is ’n voortdurende proses om tred te hou met dinamiese bedryfsveranderinge sowel as verskuiwings in belanghebbendes se verwagtinge. Die hoeveelheid spoorvervoerverkeer het onlangs beduidend toegeneem, terwyl die betrokke infrastruktuur agteruitgegaan het. Dié agteruitgang het die bedryfsrisiko’s verhoog, en lei tot ontoereikende spoorweginstandhouding en -inspeksie, wat veronderstel was om met die veranderinge tred te gehou het. Dit gee aanleiding tot ’n toename in spoorwegfoute en gevolglike ontsporing. ’n Gevallestudie is van die instandhoudingsbeleid van die Passasierspooragentskap van Suid- Afrika (PRASA) Metrorail onderneem om dié organisasie se instandhoudingstrategie te beoordeel en die moontlike kritieke foutmodusse te bepaal. Die doel hiermee was om verbeteringe in stelselbetroubaarheid en dus ook stelselbeskikbaarheid voor te stel. Op grond van die gevallestudie van die PRASA Metrorail-instandhoudingstrategie en -prestasie, word daar aanbeveel dat PRASA Metrorail sy instandhoudingsbeleid verander deur ’n klusterinstandhoudingsplan vir elke depot in werking te stel.