الفهرس | Only 14 pages are availabe for public view |
Abstract All railway administrations are intensely desired to increase the future train speed. It becomes necessary to carefully examine all items affects track and its maintenance through high speed train operation. The sort of measures will be necessary in order to ensure safety in such train operation as well as excellent riding quality ; and further, the most economical track structure and maintenance system thereof , taking into consideration the maintenance costs. On the other hand, conventional track structure consisting of long-welded rail, double elastic fastening , P.S. concrete sleepers and crushed stone ballast, was adopted. Besides various considerations are provided for high speed operation in the design of track material and maintenance. The thesis consists of four parts as follows : Part (1 ): Includes definition of the different kinds of speeds used in railway operations, characteristic of new layout, relation between centrifugal force, cant and curve radius for increasing speed in addition the influences of increasing the non-compensated centrifugal acceleration on passengers comfort. I n this connection, methods for assessing the comfort quality of passenger vehicles, measures for increasing speed by using of new suspension for car body such as pendulum or pneumatic suspensions are discussed. It also discusses types of transition curves and ramps and reasonable length of transition ramp. It also discusses permissible limits of cant gradient. Also this part includes suitable radius of vertical curve for increasing speed. |