Sir - Your February issue highlighted ’the invasion of steel sleepers into concrete territory’ (RG 2.00 p96) but gave no fully satisfactory explanation for the rapid growth in their use over the last five years.
The Concrete Sleeper Manufacturers Association (CSMA), a Product Association of the British Precast Concrete Federation, was formed last year to promote use of concrete sleepers. Its first task was to design the new G44 sleeper for 30 tonne axleloads and either UIC60 or 113A rail. CSMA’s work now also includes other concrete sleeper track development and an investigation into reasons for the rapid growth in use of steel sleepers. This has included an international survey and interviews with senior British rail industry personnel including Railtrack. It has already revealed certain reasons for the trend towards use of steel sleepers.
The article rightly states that steel is used when there is no need to reballast and that reballasting may therefore be deferred for an unknown length of time. In many of these cases Railtrack concedes that concrete sleepers could also be used without reballasting. A worrying aspect that the article ignores is what happens when the ballast does need cleaning and renewal. Not only are there no existing methods for doing this, but some engineers are adamant that steel sleepers should not be used on new (uncompacted) ballast because experience in other countries shows that it is almost impossible to maintain the necessary accuracy of level for ride quality. Will the steel sleepers therefore be replaced with concrete when reballasting is done, long before the steel sleeper is life-expired? Incidentally, the article is incorrect in stating that use of steel sleepers is widespread in Europe. They are not used by any major EU railway, and only a thousand or so are installed annually in Switzerland.
What the CSMA investigation does reveal is that Railtrack is driven by the need to meet both the Rail Regulator’s requirement for year-on-year productivity gains and also the City’s requirement for profits to help bolster the share price. Use of steel can help achieve both these targets because there is no cost of reballasting. But the expense of reballasting is only postponed - what happens to productivity gains and short-term profitability when it does have to be done, by as yet unknown methods? This short-term view could lead some to rename permanent way as ’temporary way.’ It is an odd policy for assets that should have a 50-year life from new.
Railtrack has stated its intention to prepare guidelines for use of steel sleepers. Will all the relevant factors be taken into account, including the greater future workload following their adoption and also all aspects of safety? For example, HM Chief Inspector of Railways Vic Coleman was quoted in the August 19 1999 edition of Rail Business Intelligence that ’If they [steel sleepers] were to become common in the UK we would want to consult colleagues in other countries where they are used.’ In Australia, an ’Expression of Interest for the supply of Alternative Sleeper Types for use in the Westrail network’ was issued recently. In it Westrail states: ’The light mass of the steel sleeper is seen as a concern particularly when under traffic when the bow wave that precedes the passage of a wheel can lift the steel sleeper, reducing its ability to resist lateral movement.’
Clearly the guidelines promised by Railtrack are required as soon as possible.
Leicester, Great Britain