Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation

Dissertation (MEng)--University of Pretoria, 2017.

Saved in:
Bibliographic Details
Other Authors: Grabe, P.J. (Hannes)
Format: Thesis
Language:English
Published: University of Pretoria 2017
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613480749629440
access_status_str Open Access
author2 Grabe, P.J. (Hannes)
author_browse Grabe, P.J. (Hannes)
author_facet Grabe, P.J. (Hannes)
collection Thesis
dc_rights_str_mv © 2017 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MEng)--University of Pretoria, 2017.
format Thesis
id oai:repository.up.ac.za:2263/61343
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:36:49.486Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2017
publishDateRange 2017
publishDateSort 2017
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/61343 Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation Grabe, P.J. (Hannes) u11050692@tuks.co.za VanDoorne, Rick UCTD Engineering, built environment and information technology theses SDG-09 SDG-09: Industry, innovation and infrastructure Dissertation (MEng)--University of Pretoria, 2017. The objective of this study was to quantify and determine trends in the uncertainty in the life cycle cost (LCC) associated with the maintenance and renewal (M&R) of the rail of a railway track under a fixed set of input parameters and conditions. Rail maintenance models were identified in the literature which use the mean or expected value of the input distributions to determine a corresponding mean or expected LCC. Although these models display important trends with regard to input parameters such as inspection intervals, they provide no means to quantify the uncertainty related to maintenance and renewal decisions. Thus, a numerical model was developed and programmed using MATLAB which allows the quantification of the uncertainty in the LCC estimated for a given set of conditions. The model uses Monte Carlo simulation to determine the LCC associated with the installation, maintenance and renewal of the rail. The model incorporates imperfect inspections, a hazard function for rail fatigue defects modelled using the Weibull probability distribution and a P-F interval for rail fatigue defects modelled using an exponential probability distribution. The model also allows the modelling of maintenance as either perfect or minimal maintenance as well as the use of either flash butt or alumino-thermic welds to conduct the maintenance. This allowed the development of a method to assess which weld type to use to minimise the minimum attainable mean LCC. The developed model was validated against a similar stochastic rail maintenance model from the literature. However, the model from the literature considers only the expected LCC and does not show any uncertainty related thereto. The novelty in this study therefore lies in the fact that the LCC uncertainty can be quantified in the form of a probability distribution at any given renewal tonnage for a given set of conditions. It was found that the distribution of the LCC at a given renewal tonnage followed a lognormal probability distribution. The standard deviation of the lognormal distributions fitted using the method of maximum likelihood was used as a metric to quantify the uncertainty related to the life cycle cost at a given renewal tonnage. The LCC uncertainty was found to increase with an increase in inspection interval length. Furthermore, the uncertainty was also found to increase with a respective increase in renewal tonnage. For varying inspection interval lengths it was found that the uncertainty of combined maintenance costs (planned plus unplanned maintenance costs) tended more strongly towards the uncertainty in the planned maintenance costs for smaller inspection intervals and more strongly towards the uncertainty in unplanned maintenance costs for larger inspection intervals. A critical cost ratio was found of flash butt weld cost to alumino-thermic weld cost at which the minimum attainable mean LCC was equal. It is more economical to use flash butt welding for maintenance if the cost of flash butt welding maintenance produces a cost ratio lower than the critical cost ratio. The developed model could allow railway operators to assess the risk associated with renewal of the rail at varying renewal tonnages for given conditions such as inspection interval lengths, detectability of rail fatigue defects and the arrival rate of rail fatigue defects. Civil Engineering MEng Unrestricted 2017-07-13T13:29:01Z 2017-07-13T13:29:01Z 2017-04-20 2017 Dissertation VanDoorne, R 2017, Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation, MEng Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/61343> A2017 http://hdl.handle.net/2263/61343 en © 2017 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
Engineering, built environment and information technology theses SDG-09
SDG-09: Industry, innovation and infrastructure
Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation
title Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation
title_full Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation
title_fullStr Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation
title_full_unstemmed Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation
title_short Stochastic rail life cycle cost maintenance modeling using Monte Carlo simulation
title_sort stochastic rail life cycle cost maintenance modeling using monte carlo simulation
topic UCTD
Engineering, built environment and information technology theses SDG-09
SDG-09: Industry, innovation and infrastructure
url http://hdl.handle.net/2263/61343