Preliminary results and conclusions from the experimental monitoring of thermal regime of railway track structure

Abstract

The article describes the preliminary results and conclusions of experimental monitoring of the thermal regime of railway track structure performed on the experimental stands (railway track models in 1:1). The purpose of this study was to optimize the structural thickness of the protective layer in the subgrade structure. The first part of the study describes the experimental stand design and methodology for monitoring the heat and humidity variations in the railway track structure. The following parts describe the results of verification of the thermal characteristics of the material incorporated into the model of the railway track and of its subgrade.

Preliminary results and conclusions from mathematical modelling of thermal regime of railway track structure

“…Day 97 (TIME = 97) matches the date 19.02.2015, when the maximum frost depth D F of the monitored structure was reached. Figure 5 clearly shows that the depth of freezing on the railway track model correlates with the depth of freezing reached in the experimental stand structure D F = 0.41 m (see [1]) and the position of the zero isotherm can be located in the ballast bed area.…”

“…The second part of our research (Department of Railway Engineering and Track Management -DRETM) [3] characterizes the results of mathematical modelling of the thermal regime of the railway track model and subsequently carries out a comparison of results of experimental measurements [1] and mathematical modelling. It also introduces the preliminary design nomogram for determining the structural thickness of the protective layer of subgrade surface.…”

Updating the Design Map of Frost Indexes as a Prerequisite for Relevant Assessment of Track Substructure for Non-Traffic Load

“…As mentioned above, the update of the design map of air frost indexes I Fd is only a partial output of the experimental activity at the Department of Railway Engineering and Track Management. The parallel research activities include updating the design map of average annual air temperatures [3], experimental monitoring of real railway track structure models [7], verification of thermo-technical parameters of selected building materials [8], and numerical modelling of various track substructures SoilVision software [9]. Moreover, further activities are conducted, with the aim to determine the input data for updating the design nomogram and the necessary update of the track substructure dimensioning methodology for the non-traffic load, included in the legislative document [1].…”

Experimental monitoring and numerical modeling of thermal regime of railway track structure - preliminary results and conclusions

“…other characteristics (all were tested by our laboratory in Kupčuliak 2011, Dobeš 2015, and Ižvolt et al 2016, namely:…”

“…The SoilVision software (Saskatoon 2016) enables numerical modeling of various combinations of material compositions of railway track structure after entering all the relevant input data (Hodas Ižvolt Dobeš 2016). In this way conditions for drawing up the relevant design nomograms for various types of subgrade structure or railway body types are created.…”