Change search
ReferencesLink to record
Permanent link

Direct link
A study of the rail degradation process to predict rail breaks
2006 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

Rail infrastructure is a large and costly investment, and has a long life. To realize the benefits from this investment, effective maintenance is required. Railways are one of the prime modes of transportation in many countries and as they are closely associated with passenger and cargo transportation, they own high risk in terms of potential loss of human life and damage/destruction of assets. New technologies and stringent safety standards are constantly being introduced, but accidents still occur. There will always be some risk associated with derailments and collisions, but it can be reduced by elimination of the root causes by means of an effective maintenance strategy to govern optimization of inspection, lubrication and grinding frequency and/or improvement in skill and efficiency. A detailed study of the defects which emerge both in the rolling stock and the rail infrastructure is essential to identify the correct maintenance strategy. Detection and rectification of rail defects/degradations are major issues for all rail players around the world. Some of the rail degradations include worn out rails, weld problems, internal defects, corrugations and rolling contact fatigue (RCF) initiated problems such as surface cracks, head checks, squats, spalling and shelling. If undetected and/or untreated, these defects can lead to rail breaks and derailments. Efficient maintenance strategies can reduce potential risk of rail breaks and derailments. A potential risk is the risk which accumulates in the form of rail degradation over a period of time. In spite of continuous efforts made by all rail infrastructure operators around the world to reduce costs, a substantial proportion of railway budget is spent on rail maintenance. It is understood that the consequential costs due to derailment reduces with increase in inspection, lubrication, grinding and replacement costs. The challenge is to find a balance between the maintenance costs which consists of inspection, lubrication and grinding costs, and consequential costs due to derailments. The consequences of derailment in terms of loss of human life, damage/destruction of assets and loss of company trust and reputation justify maintaining stringent safety standards, which require massive rail maintenance investments in order to be met. Reduction in maintenance investments may increase the rate of rail degradation, which may increase the risk of derailments. The aim is to develop an approach to predict rail failures, which will help to optimize maintenance activities (inspection, grinding, rectification/replacement and/or welding). Generally, there is a trade-off between maintenance investment and the risk involved in rail degradation in order to develop a rail maintenance procedure. Failure prediction of rail sections undergoing degradation will help to estimate the risk of derailment. Thus, prediction of the rail failure rate is a requirement for the development of an effective rail maintenance procedure. Different types of rail degradation processes leading to various rail defects have been studied. The performed literature studies indicate a need for better prediction of rail failure over a period of time based on the factors influencing rail degradation. The maintenance strategy followed by the Swedish National Rail Administration (Banverket), Sweden's rail infrastructure operator, is described and the issues related to rail degradation and maintenance are outlined for further research in this area. Rail failure data has been extracted from different Banverket's databases, classified according to a classification framework developed and analyzed over a period of time based on Million Gross Tonnes (MGT) of traffic using Weibull distribution. During the process of data evaluation and analysis, a method of extracting useful information from incomplete data has been identified.

Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2006. , 76 p.
Series
Licentiate thesis / Luleå University of Technology, ISSN 1402-1757 ; 2006:73
Research subject
Operation and Maintenance
Identifiers
URN: urn:nbn:se:ltu:diva-18226Local ID: 7814e960-89f9-11db-8975-000ea68e967bOAI: oai:DiVA.org:ltu-18226DiVA: diva2:991233
Note
Godkänd; 2006; 20061212 (ysko)Available from: 2016-09-29 Created: 2016-09-29Bibliographically approved

Open Access in DiVA

fulltext(1243 kB)3 downloads
File information
File name FULLTEXT01.pdfFile size 1243 kBChecksum SHA-512
2fec132924d5cf6f9523696237816d268942dffb9801846fa8041ab807da6822c274d06f6879793c7614a8581019080825199ae29d4be39df5e7b19d643125a6
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Kumar, Saurabh

Search outside of DiVA

GoogleGoogle Scholar
Total: 3 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 7 hits
ReferencesLink to record
Permanent link

Direct link