VEGA 2020-2023 DRETM
VEGA 1/0084/20 prof. Ing. Libor Ižvolt, PhD. - responsible project manager
Scientific grant agency of the Ministry of Education of the Slovak Republic
Solution time: 1.1.2020- 31.12.2023
Numerical and experimental analysis of the transition zones of the structures of the railway superstructure and objects of the railway sub-structure
The subject of the project solution is the design and verification of the constructions of the transition areas between the railway constructions. upper body and objects of the body. the bottom as places of a significant change in the stiffness of the driving track. By applying the methods of numerical modeling and experimental analysis, the predicted maximum load values at the individual interfaces of the structural layers of the proposed transition areas are obtained, for different cases of the construction of the railway. top (classic and unconventional), body objects, etc. bottom (bridges, culverts, underpasses, tunnels) and different structural composition of transition areas (modification of structural elements of the rail grid and materials of the structural layers of the rail bottom) with regard to maintaining the required deformation resistance of the rail structure. track during its lifetime. The verification of the selected designs of transition areas will be carried out by experimental measurements of tension in individual structural layers and by monitoring the geometry of the track in the entire area of interest of the selected modernized sections of the tracks.
Solution time: 1.1.2016 do 31.12.2019
Optimization of the subgrade structure from the aspect of non-traffic load
The aim of the presented project is the experimental and mathematical verification of various applications of materials in the structural layers of the railway track (subgrade) from the aspect of their thermo-technical properties and thermal resistance. The theoretical analysis of these questions will be based on experimental laboratory research (test stand - model of a railway track in m 1:1) supported by the results of mathematical modeling using the available software environment (SoilVision SVHEAT) The result of the project solution should be an objective and reliable design of the construction of the railway track subsoil) from the aspect of stress due to non-traffic loads (primarily the action of frost and water) in the relevant climatic conditions. The design of the optimal construction of the subgrade should also meet the requirements of the economic and technological design of its implementation and maintenance and also respect the accepted European standards in the field of railway construction, material engineering and geotechnics. Part of the solution to the task will be the optimization of the design of the subgrade structure and the technological procedures for the establishment of the subgrade structure with a built-in heat-insulating structural layer (it is assumed to apply foam concrete) both for new sections of tracks, but also for sections of tracks that are expected to be reconstructed or modernized.
VEGA 2021-2024 DGE and DRETM
VEGA 1/0643/21 prof. Ing. Libor IŽVOLT, PhD. - deputy project manager
Scientific grant agency of the Ministry of Education of the Slovak Republic
Solution time: 1.1.2021-31.12.2024
Analysis of spatial deformations of the railway track targeted by terrestrial laser scanning
Laser scanning is one of the non-contact, fast and accurate geodetic methods, with a highly detailed output. Over the years, it has found wide application in the field of spatial terrain modeling, in engineering geodesy in the measurement of natural, construction, industrial and transport objects and structures, where possible landslides, displacements or deformations can be detected thanks to the achieved millimeter accuracy. In traffic construction, the so-called method is already practically common nowadays. mobile scanning, when data on the current state of a transport structure or object is obtained from a mobile carrier. Its output is a numerical record of a specific geometric parameter of the track or a 3D model of the entire structure. However, the challenge still remains in the field of determining deformations, when the classic method of analyzing deformations from discrete points is no longer sufficient, but it is necessary to move to the comparison of either digital models, mesh models or develop a numerical analysis methodology with high accuracy. And the aforementioned challenge is the content of the project.
VEGA 2017-2020 DGE and DRETM
VEGA 1/0275/17 prof. Ing. Libor IŽVOLT, PhD. - deputy project manager
Scientific grant agency of the Ministry of Education of the Slovak Republic
dátum riešenia: 1.1.2017-31.12.2020
Application of numerical methods in defining the change in the geometrical position of the track
The essence of the project is in the numerical solution of the change in the geometric position of the track (GPK), built on a fixed running track (PJD), caused by the operational load of the track. GPK changes will be determined from absolute and relative diagnostics during the entire project implementation period, and the measurements will follow up on PJD monitoring, implemented before the project started. The focus of numerical solutions is on the application of linear and non-linear regression, deformation analysis, kinematic model and parameter estimation methods, e.g. least squares methods, robust estimations, maximum likelihood methods, etc., as mathematical tools for defining directional and height differences from the baseline measurement stage or projected state. The necessity of applying numerical solutions results from the use of combined point and continuous measurement technologies. When choosing a methodology for processing and analyzing measurements, the main priority is to preserve the basic parameters of data quality, accuracy, reliability and objectivity of the results.
