current practices in railway track analysis and design are reviewed and discussed in this paper. the mechanical behavior of railway track structure comprising of various components has not been fully understood due to the railway track structural complexity. although there have been some improvements in the accuracy of current track design methods in recent decades, there are still considerable...

the main design criteria of ballasted railway tracks include rail deflections, rail bending stresses, rail wheel contact stresses, sleeper bending moments and ballast sleeper contact pressures. numerous criteria have been defined for the design of ballasted railway tracks owing to the various mechanical properties of track components and their complex interaction. therefore, railway track desig...

The main design criteria of ballasted railway tracks include rail deflections, rail bending stresses, rail wheel contact stresses, sleeper bending moments and ballast sleeper contact pressures. Numerous criteria have been defined for the design of ballasted railway tracks owing to the various mechanical properties of track components and their complex interaction. Therefore, railway track desig...

this paper deals with the threshold radius that warrants the use of single restraining rail for transit and railroads. different railways use different threshold radius from 91m to 365m to provide restraining rail. these threshold figures are probably experience driven choices. the need for restraining rail may be related to a so-called derailment alarm coefficient of 1.2 sustained over 2m leng...

Thorough understanding of steel rail response to wheel load is a key step towards design and evaluation of the railway track structure. In current practice, maximum vertical deflection and bending moment are calculated using the theory of infinite beam on continuous elastic foundation (Winkler model), in which the foundation stiffness is assumed as constant. However, variation of track modulus ...

The paper investigates systems thinking and systems engineering. After a short literature review, the paper presents, as a means for systems thinking, twelve thinking tracks. The tracks can be used as creativity starter, checklist, and as means to investigate effects of design decisions taken early in the process. Tracks include thinking about time, risk and safety, and different types of life-...

This paper presents a model-based control design for trajectory tracking of two-wheeled mobile robots based on Linear Quadratic Regulator (LQR) optimal control. The model proposed in this article has been implemented on a computational model which is obtained from kinematic and dynamic relations of KHEPERA IV. The purpose of control is to track a predefined reference trajectory with the best po...