The Use Of Life Cycle Cost Analysis In Determining The Cost Effectiveness Of Railway Lines’ Design And Maintenance Options For Railway Lines Through Windblown Sandy Desert In Namibia “Case S

ABSTRACT

Railway transport in Namibia is one of the most important mode of transport with great importance to the economy of the country. Currently, road networks are the most important because of the low population density of the nation. However, railway lines have been reported to be the most economical, efficient, environmentally friendly, and the safe solution for long distance transportation of heavy goods [1]. The Namibian Railway Network lines linking to the coastal towns and ports, i.e. Swakopmund-Walvis Bay and Aus-Lüderitz Railway Line, are passing through the Namib Desert. Deposit of wind-blown sand onto the railway lines poses a great challenge to the maintenance and operations of this lines. The challenge for decision-makers is which solution is cost-effective to implement in the Namibia context to solve the problem. It has been reported widely [2, 3, 5, 7] that the best way to evaluate the cost effectiveness of different solution is by using the Life Cycle Cost Analysis (LCCA) approach.

The main objective of this study is to use LCCA, as an engineering economic tool, to determine the cost-effectiveness of the options to the challenging wind-blown sand on the railway lines passing through the desert. Specific objectives are: 1) Identify the best infrastructure design options and technical maintenance solutions for mitigating the sand problem onto the tracks. 2) Use the LCCA to evaluate the cost-effectiveness of the different solutions in order to recommend the best strategy. The study has exploded the knowledge of the LCCA of railway infrastructure in Namibia for both the analysts and decision-makers.

This study has presented a good insight of the LCCA as one of the best systematic approach to use to guarantee the best performance of the railway system. Ultimately the LCCA was successfully employed in the study to determine the cost-effectiveness of the

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solution(s) to combat the challenge of sand ingress onto the railway line. In the LCCA process, different alternatives were identified, discussed and analysed; which includes both railway infrastructure design solutions and technical mitigation measures. The LCCA results presented the Humped Slab Track to be the cost-effective solution compared to all other alternatives. However, it was further discussed that this option is only ideal for the sections where dynamic dunes are not crossing. This has proven that in as much as LCCA is a good engineering economic tool, it needs to be coupled with viability criterion/criteria in order to determine the cost-effectiveness of the design and maintenance solutions to combat the challenging problem of wind-blown sand on the railway line passing through desert areas. The study further proved that Tubular Track system was cost-effective compared to the Conventional Track system. The study provides a good insight of analysis to prove that Tubular Track system covered in the Tunnel System is the most viable and cost-effective solution to the sand problem along the dune belt. A number of recommendations for future improvement(s) and further researches were also proposed.