For about 150 years, the steel rail has been at the very heart of the world's railway systems. The rail works in a harsh environment and, as part of the track structure, it has little redundancy; thus, its failure may lead to catastrophic derailment of vehicles, the consequences of which can include death, injury, costs and loss of public confidence. These can have devastating and long‐lasting effects on the industry. Despite the advances being made in railway permanent way engineering, inspection and rail‐making technology, continually increasing service demands have resulted in rail failure continuing to be a substantial economic burden and a threat to the safe operation of virtually every railway in the world. This paper presents an overview of rail defects and their consequences from the earliest days of railways to the present day.

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A simple, reliable, and repeatable method has been developed for determining dynamic plane-strain fracture toughness using an on-specimen strain gage. This extends the range of the British Standard Method for Determination of the Dynamic Fracture Toughness of Metallic Materials (BS 6729) to include measurement at impact testing rates. Dynamic finite element computing was used to optimize the position of the gage on the specimen. In tests at low loading rates on Charpy specimens, good agreement was found between toughness values calculated from the applied load and the calibrated gage, and with those measured by the shadow optic caustic technique. At higher rates, several gage types and two adhesives were compared. A satisfactory method was developed for performing tests at high and low temperatures. The technique was applied to larger bend specimens of two steels, and a test program was conducted at seven laboratories to assess the influence of testing machine and instrumentation variables. From the results, a standard calibration and test procedure has been developed.

Many problems with rails can be attributed to the failure of the steel to withstand the service environment. The successful selection of new and better materials depends upon accurate material evaluation. Realistic laboratory techniques adopted at British Railways for studying material behavior are described in detail, and various results for currently available rail steels are given. The future development of rail steels based on these evaluation methods is discussed.

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A major source of cost saving in the approach to conversion presented by Mr Cannon was the avoidance of rail cropping. A number of speakers queried this practice, given the difficulties it presented of battered rail ends, quality control of welding, cleaning etc. It was suggested that cropping could be cost-effective. Mr Cannon stated that his cost analysis had been based on the assumption that there was to be minimal disturbance to normal operations and that conversion work would be undertaken during the night. In many cases a good quality product could be produced, at a rate typical of the normal welding cycle time, without end cropping. In such cases it was difficult to see how cropping could turn out to be more cost-effective.

Part 1 of the European Rails Standard, concerning flat-bottom symmetrical railway rails, is being developed by Working Group 4 of the CEN Railway Applications Techntcal Committee TC 256. Its probable requirements for quality assurance and inspection, steel manufacture and grades, qualifying tests, and the new or modified acceptance tests, are outlined. Attempts are being made to introduce many performance-related aspects.

This Technical Note outlines some of the work undertaken by British Rail Research (BRR) on the viability of joining together existing bolted rail to create continuously welded rail.