Rail weld geometry and assessment concepts

Weld defect formation in rail thermite welds

A previously developed heat transfer model is used to study the influence of welding parameters on weld defect development in thermite welds. Weld defect formation maps are constructed from a series of heat transfer simulations. For the current normal rail thermite welding conditions, it is found that shrinkage cavity formation can be avoided but cold-lap and centre-line defects are likely to o...

Optimal Maintenance and Renewal Strategy Due to Rail Track Geometry

Neurofuzzy model-based predictive control of weld fusion zone geometry

A closed-loop system is developed to control the weld fusion which is specified by the topside and back-side bead widths of the weld pool. Because in many applications only a top-side sensor is allowed which is attached to and moves with the welding torch, an image processing algorithm and neurofuzzy model have been incorporated to measure and estimate the top-side and back-side bead widths bas...

Words, Concepts, and the Geometry of Analogy

This paper presents a geometric approach to the problem of modelling the relationship between words and concepts, focusing in particular on analogical phenomena in language and cognition. Grounded in recent theories regarding geometric conceptual spaces, we begin with an analysis of existing static distributional semantic models and move on to an exploration of a dynamic approach to using high ...

Relation between the geometry of rail welds and the dynamic wheel–rail response: numerical simulations for measured welds

The primary mechanisms playing a role in the dynamic wheel–rail response to rail weld irregularities in a ballasted track are pointed out. The concept of P1 and P2 forces for metallurgical rail welds, introduced in a first paper [1] concerning the present research, is further elaborated. The dynamic wheel–rail response is simulated for a number of geometrical rail weld measurements. Results sho...