الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The sab track is a new technology in the railway transportation world to cope up with the increasing axle loads and high speed. The most common slab track systems in the world are BÖGL, Shinkansen, and REEDA 2000. One of the most modern methods to analyze the railway tracks is the Finite Element Method (FEM). FEM can represent the realistic railway lines in a numerical model to analyze/design these tracks. This research aims to analyze, compare between different types of railway slab track systems, as well as to develop a proposed model to design railway slab track system. The slab track elements have been introduced. A comparison between the slab track and the ballasted track has been carried out. The different types of the railway slab track have been analyzed, the construction methods of the railway slab track have been also discussed. Finally, a proposed slab track design model has been introduced using the Finite Element software Midas GTS NX and validated. The linear and nonlinear behavior of the slab track systems have been investigated. New design equations and graphs have been obtained through a parametric study to describe relationship between the rail deflection and the modulus of elasticity for subgrade and replacement, and the thickness of replacement layer. The application of the proposed slab track design model on the most common slab track systems has shown that the European Norms (EN) are more conservative than the American specifications (AREMA). The analysis of the most common slab tracks has ensured that the rail deflection limit is the most crucial criteria for EN specifications while the subgrade stresses are the most vital factor for AREMA specification. The comparison between the slab track design models of the most common type (BÖGL, Shinkansen, and RHEDA 2000) has indicated that the most efficient slab track system is RHEDA 2000 as it has showed the least values regarding rail deflection, rail stress, replacement and subgrade stresses which means that it has better stability and stiffness. Furthermore, the comparison between the linear and nonlinear modelling techniques of slab track systems has illustrated that studying the substructure of the slab track should be performed in nonlinear analysis for good, medium and weak soils but it can be carried out in linear-elastic analysis for very good soils such as rocks and gravel. However, studying the superstructure of the slab track can be performed with linear-elastic analysis to save both efforts and time. The parametric study for the most common slab track systems has deduced the 1st design aid charts and equations for the slab track systems, these charts and equations can be used to design any slab track regarding the allowable rail displacement. The EN parametric study has figured out that the minimum modulus of elasticity for subgrade soil to fulfill the rail deflection criterion without a formation soil must be taken as 127, 143, and 128 MPa for BÖGL, Shinkansen and RHEDA 2000 respectively, and for AREMA parametric study, it can be taken as 62, 70, and 59.2 MPa for BÖGL, Shinkansen and RHEDA 2000, respectively.