Bankonstruktionens egenskaper och deras påverkansgrad på nedbrytningen av spårfunktionen

Karin Edvardsson

The main objective of the report is to identify the characteristics that influence the degradation; defined as the condition change, of the super- and substructure of the railway construction. The objective is also to rate the degree of influence of these properties as well as give an account for the effect relationships to the extent that this is possible. In Sweden there are currently about 15,000 km of railway, of which 13 600 km are administered by the Swedish Transport Administration. For this railway facility, there is today a lack of overall maintenance strategies that describes how the maintenance should be carried out for optimal cost efficiency. There is therefore a need to improve the ability to assess the condition and predict the future condition development for different track types in a lifetime perspective. First of all, basic knowledge regarding the condition data collected today and a comprehensive identification of the degradation characteristics affecting the railway facility, as well as the degree of their influence and their effect relationship, are needed. Identified degradation properties include such that affect the super- and substructure but does not include switches, ducting, electrical systems, signal systems or telecommunication. To create reliable life cycle cost models, that enable prioritization and planning of maintenance operations in a cost optimal way, focus on the data inputs to the model is required. Many components of the railway system have complex degradation processes. It is also important, when choosing maintenance strategy, to look at the parts that are associated with high costs, where both the cost of operation and frequency of operation are considered. The greatest impact, of the properties assessed to affect the degradation of the railway construction, has traffic load; where both the load and the frequency are of importance. Then follows, in descending order; drainage, the drainage system, degradation of ballast, rails and sleepers, ballast pollution, track geometry (curves and joints), presence of joints, subgrade stability and vehicle characteristics. The project was done as a comparative study, where degradation properties and effect relationships identified through literature studies have been compared with the corresponding results obtained by qualitative studies, i.e. interviews with experts in the field.



Open seminar with Mistra SAMS international scientific advisory...

Mistra SAMS international scientific advisory panel (ISAP) is visiting Stockholm, and the program will host an open seminar where the panel members will give talks in their area of expertise.

ERPUG 2017

The five year anniversary of  European Road Profile Users' Group (ERPUG) Forum will take place at Ramboll head quarter, Copenhagen, Denmark October 19-20, 2017. 



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