Experimental Monitoring of Moisture Conditions in the Various Types of Track Bed Structure

Abstract

The principle of designing the railway track structure is based on two baseline assessments. The first assessment verifies the resistance of the railway track structure against the traffic load, which is represented by static and dynamic effects from rail transport. The assessment of railway track structure against the non-traffic load is also important for the correct and relevant design of railway track structure. This load is represented by climatic factors such as frost, water, wind and sunlight. The paper presents the results of experimental monitoring of moisture conditions in the various railway tracks structures. The experimental stand Department of Railway Engineering and Track Management (DRETM) was built for this purpose. The monitoring of thermal regime and water regime of railway track is carried out at this experimental workplace. In the introductory part of the paper are presented individual measuring profiles of the experimental stand DRETM, which were progressively built in a scale 1:1, during the past 7 years. The experimental stand DRETM consists of 6 measuring profiles, which differ from each other by track bed structure and shape of track substructure. The measurement of moisture conditions in individual measuring profiles was performed by a non-destructive method using a TDR test probe. The next part of the paper presents the measured results and the evaluation of the moisture conditions (variation of the moisture conditions) in the individual measuring profiles of the experimental stand DRETM. The final result of this experimental monitoring is represented by the design moisture values of the individual building materials applied to the track bed structure. Subsequently, these moisture values serve for numerical modelling of the non-traffic load on various railway tracks structures.