الفهرس 
Chapter 1 : IntroductionOnly 14 pages are availabe for public view
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Abstract
One of the important considerations in the design of high-speed railway tracks is its lateral stability specially at the positions of horizontal curves. The objective of this research is to investigate the role of the different factors which affect lateral ~\splacements of railway track.
The following factors were investigated in detail: - Sleeper type.
- Shoulder width.
- Type of soil.
An analytical model was developed to represent the track and to calculate the lateral displacements. The proposed mathematical model is concerned with curved rails and treats the ties resting on the ballast material as plates on Winkler foundation naving stiffness 1<. Furthermore, a modulus of ballast friction krr havi ng the same value for longitudinal and lateral track displacement based on Winkler assumption is laken into account. The rails are presented as continuous beams connected to the ties oy means of fasteners that are sufficient to transmit safely the load between rails and ~Ieepers. The displacements in all three directions and the rotation about curved XXaxes of curved rail and rotation about vertical Z-axis only are considered as boundary conditions for the rail element. However, the rotation about Y-axis is considered free.
It was found that one-block sleepers provide greater lateral resistance wmpared to two-block sleepers. Also, it was noticed that soil properties of ballast are lillong the most effective factors to the lateral resistance of railway traffic especially U1 high-speed trains with heavier carriages and increased traffic frequency. However, ~le effect of shoulder width to lateral movement was found to be of smaller values.
Finally, the proposed model was used on find the nonlinear relationship oetween the lateral displacement of the track and the speed of the moving trains in urved tracks taking into consideration superelevation of rails and different shapes of track geometry.