COST EFFECTIVE MEASURE FOR TRACK IMPROVEMENT. Phil Anderson and J. S. Mundrey

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1 Page 1 of 5 TRANSPORTATION, WATER AND URBAN DEVELOPMENT DEPARTMENT THE WORLD BANK March 1995 Transport No. RW-11 COST EFFECTIVE MEASURE FOR TRACK IMPROVEMENT Phil Anderson and J. S. Mundrey Some developing country railways maintain track by traditional manual measures using hand tools, while other railways rely on mechanized measures with on-track machines just like those used in developed countries. An evaluation of benefits of mechanized measures that merely accounts for labor savings may not justify measures which actually are cost effective. This is especially true of heavy traffic lines where a benefit exists from increased capacity, due to the application of higher-quality mechanized measures that minimize track occupancy and maximize intervals between periodic maintenance. Benefits of advances in track component design and mechanized maintenance technology also should be evaluated. The conclusion for most railways will be that traditional, manual track improvement measures are economically obsolete. The World Bank has provided assistance to railways in several countries, including India, China, Poland, and Senegal, to introduce mechanized measures for track improvement like those used on North American, Japanese, and European railways. The mechanized measures replace traditional manual measures (see Box). TRADITIONAL VS. MECHANIZED MEASURES Using traditional manual measures, ballast compaction is unsatisfactory for normal speed since ballast is not packed.under load. For example, as repeatedly operate over :he track and compact the ballast after deep cleaning, manual packing of soft spots is also necessary. (Indian Railways requires four complete packings during the 21 days before normal speed is restored.) Whenever complete track renewal (CTR) is carried out to replace rail, crossties, and ballast, cost effective track components and materials should be installed. The most important cost effective component will inevitably be welded rails because they eliminate rail joints and can reduce maintenance costs by as much as 50%. During CTR the transfer to the site of welded rail and concrete crossties will be mechanized to some extent because of the difficulty of moving these components by labor alone and the risk of damage in handling them manually. On hightraffic lines, CTR might even employ a mechanized track lines, CTR might even employ a mechanized track-laying machine that both removes the old rails and crossties and installs the new components. Traditional Measures Using traditional manual measures, basic (routine) track maintenance is performed by a local gang and includes inspection of rails and other track components; tightening and oiling of components; replacement of crossties and rails, cleaning of ditches and culverts; and removal of weeds and brush. The gang may line and level the track with "beater packing" (using a special pick-axe to ram the ballast under and around the crosstie) or "measured shovel packing" (using a shovel to place ballast under each crosstie).

2 Page 2 of 5 In addition to basic maintenance, the local gang may undertake shallow cleaning of ballast in the area between (but not under) the crossties. Deep cleaning of ballast, by contrast, is usually done by gangs of workers and involves removal of all ballast under the crossties, screening it to remove fines, replacing it along with new ballast as necessary, and manually lining and leveling the track. Since packing and cleaning are strenuous work, labor productivity is low and turnover high. Once track is renewed with welded rails and concrete crossties, most railways will decide to mechanize subsequent routine maintenance such as tamping, lining, and surfacing. This is because beater packing can easily damage concrete crossties and shorten their life. INDIAN RAILWAYS TRACK MODERNIZATION The Bank's Third Railway Modernization Project, which is financing part of Indian Railways' needs for rails and track machines, illustrates the change from traditional to mechanized measures. Its objectives are to: modernize track maintenance by introducing cost effective on-track machines; install stronger, more durable rails on primary main lines; and establish a track maintenance planning and control system to support need-based maintenance. The original loan was for $390 million, but over one-third was canceled, due mainly to Indian Railways' decision to stop importing rails (sea Box). Quality of Indian Rails Indian Railways historically obtained rail mostly from a domestic producer. Strength was 20% less than the European standard of 90 UTS, and its life was shorter. In the Third Railway Modernization Project, 258,000 tons of rails were procured out of 480, 000 tons originally planned - all from overseas suppliers. But the initial cost of the imported, higher-quality rail with customs duties was greater than that of domestic rail. Budget constraints led Indian Railways to stop importation and procure rail from the domestic producer. Almost all rails being laid on heavy density routes now are of 90 UTS quality, including rails supplied by domestic producer But domestic rails don't meet the standards for dimensional tolerances and end straightness, some rail steel is still not produced by the continuous casting process, and de-gassing equipment and in-line ultrasonic testing equipment are not being used. The successful track machinery component financed 130 machines costing $133 million, including track-laying machines, ballast cleaning machines, crosstie changing machines, ballast regulators, continuous tramping machines, dynamic track stabilizers, mobile turnout changing gantry cranes, and flash butt welders. However, benefits of the rail component were less than expected since Indian Railways now is installing lower quality, less durable rail. In comparison, quality and durability of other track components -- concrete crossties, fasteners, and turnouts -- are satisfactory. Indian Railways also was to acquire technology for track geometry recording cars to provide reliable data for the track maintenance planning and control system being developed under the project. The planning and control system would include threshold values of track geometry parameters and allow long term planning as well as short term evaluation and control of field track maintenance. Progress of this component has been unsatisfactory. The Indian project shows that, without better rail and a maintenance planning and control system, the potential benefits of the machinery investment cannot be realized. The Indian project raises three questions that need to be answered to evaluate proposed mechanized measures:

3 What minimum measures are required for safe operations? What additional measures are cost effective? How should cost effective measures be implemented? Page 3 of 5 WHAT MEASURES ARE REQUIRED FOR SAFE OPERATIONS? The standards for track geometry and the strength and condition of track materials and components will largely determine what measures are cost effective for improving track to permit safe operation at a given train speed. Many railways with light traffic, jointed rail, and wood crossties can and do insure a safe operation with manual measures and small hand tools. However, railways with heavier traffic, welded rails, and concrete crossties are likely to find that even to maintain minimum safety levels will require mechanization of track laying, lining, and tamping. This is partly because of the difficulty of installing and removing welded rails (which are hundreds of meters in length) and concrete crossties (which weigh over 300 kg). Also, manual measures for improving line and surface for track laid with welded rails and concrete crossties are not only difficult but unsafe. Thus, special precautions must be taken during and after manual packing, and deep cleaning to insure that lateral forces in welded rail caused by thermal expansion and contraction do not shift the track out of line. What is "safe" railway track? What standards are required for maintenance of gauge and other geometric parameters to insure a safe operation? The answers depend on the interaction of the locomotive and rolling stock with roadbed and track components at required speeds, axle loads, and tonnage. Knowledge of the strength of materials as well as judgment are needed. But typically there has been no evaluation of the risk of accident against the cost of maintaining track to different alternative minimum track safety standards (see Box). Safety Standards for Track Gauge To illustrate different standards by which railways define "safe track," the standard for safe track gauge tolerance can be compared for the U.S., India, and China. The U.S. Federal Railway Administration defines minimum track safety standards that include a gauge tolerance on tangent and curved track for passenger speeds of 96 km/h that is plus 32 mm and minus 13 mm. In India the tolerance regardless of speed on tangent track is plus 6 mm and minus 3 mm. On curves over 400 m radius, it is plus 15 mm and minus 3 mm. China has a "no-load" gauge tolerance regardless of speed for all main tracks of plus 6 mm and minus 2 mm. The tighter tolerances in China and India can cause higher construction and maintenance costs. WHAT ADDITIONAL MEASURES ARE COST EFFECTIVE? Beyond the measures required for safe operation, it is necessary to evaluate the cost effectiveness of many options for mechanized measures and new materials and components. Evaluation should be in the context of the introduction of a need-based maintenance system where isolated surface and line problems are corrected by efficient machines when ride quality or geometry falls below a specified standard. Lack of data can make cost effectiveness difficult to evaluate. An example was Pakistan Railways' decision on several lines to retain jointed rail rather than lay welded rail after concrete crossties were installed. Use of concrete crossties under jointed rail is destroying the concrete joint crossties and damaging rails at the joints. Budget constraints may have been the excuse for not installing welded rail, but the decision to postpone welding lacked data on the benefits of eliminating rail joints on concrete crossties. In fact, most railways ban jointed rail on concrete crossties. If data is available, mechanized measures may produce benefits from increased transport capacity on heavy traffic lines, which traditionally have been maintained manually between trains with little disruption of traffic. After introduction of mechanized measures, time for maintenance must be made available for use of on-track machines. These 'windows' must be long enough to economically utilize the expensive machines, but not so long as to impair train movements. Thus, if a five hour window is provided for mechanized ballast cleaning, the resulting lost transport capacity must be offset by a reduction of maintenance time and a gain in capacity by extending time intervals between ballast cleanings.

4 Page 4 of 5 New materials and components introduced by railways in developed countries have included stronger and harder rails, improved designs of concrete crossties, better fasteners, asymmetrical switch points, all-welded turnouts, and (most important) better ballast (see Box). In addition, rail welding procedures have been improved, and rail grinding and lubrication have extended the fatigue life as well as the durability of rail. Importance of Good Ballast One of the authors led a study in 1975 by a team of U.S. railway chief engineers for the Secretary of Transportation that evaluated rehabilitation needs for the bankrupt Penn Central Railroad. On Penn Central's main tracks, insufficient welded rail was laid on inadequate crossties and roadbed, except at stations where nothing had been done and speed slow orders were applied for safe operation over bad track. Rail was worn out, crusade condition was either barely adequate or unsafe; and ballast was insufficient fouled, and cemented. The subgrade had failed in many cases, causing costly derailments. With the needs for rehabilitation this implied, a key recommendation by the chief engineers was to discontinue use of a soft limestone ballast and apply instead on principal main lines a harder, more expensive granite ballast hauled in special trains from a few high-quality quarries. The chief engineers viewed ballast quality as the key to rehabilitation, and their recommendation was accepted by Penn Central and the Secretary. Better-quality materials and components allow North American railways, for example, to use rails of pounds/yard (65-70 kg/m), for axle loads of 30 metric. tons or more. This contrasts with use of rail of 75 kg/m in Russia where axle loads are two-thirds those of North America. The U.S. railroads found it was more cost effective to introduce a variety of better materials and components rather than merely to install heavier rail. HOW SHOULD COST EFFECTIVE MEASURES BE IMPLEMENTED? Should track improvement be carried out by the operating railway's own forces, by a separate infrastructure ownership and maintenance company, or by a private contractor specializing in track maintenance who is responsible to the railway? Obtaining spare parts for track machines may be a problem, or there may be a shortage of investment capital. for machinery or qualified labor for specialized maintenance. In Senegal and Cameroon, for example, there was interest in using private contractors mainly for mechanized tamping because the railways were unable to effectively maintain and operate track maintenance machines themselves. Excellent results were obtained from contracting out work to the private sector. Introduction of new materials and components should be combined with introduction of mechanized methods since the cost effectiveness of mechanized methods will depend greatly on the materials used. An example is China Railways (see Box). The Bank has assisted China Railways in meeting part of their requirements of rails and track machines, including imported premium, heat-treated and alloy rails and track machines for tamping, ballast cleaning, and other purposes. CONCLUSIONS North American railways justified mechanized measures for track improvement by their labor savings. But on the railways of developing countries, the unit cost of labor is comparatively much lower. Even considering the lower physical labor productivity in developing countries, labor savings by themselves may not justify investment in mechanized measures. A proper evaluation of mechanized measures can be difficult since it must estimate the effect on maintenance cycles of higher-quality mechanized measures, of track materials and components with longer lives, and of maintenance standards whose cost effectiveness is uncertain. Railways need to adopt a system approach to improve the standards for maintenance, the planning and control of maintenance, and the strength and durability of track components and materials. Integrated implementation of all aspects of a track modernization project is essential, including especially the provision of appropriate numbers of adequately trained personnel to operate and maintain the mechanized fleet as well as to manage the new type of

5 Page 5 of 5 maintenance programs. finally, sufficient annual funds must be made available to procure spare parts, Maintain equipment, and train qualified personnel. The Challenge for China Railways In 1993 the Ministry of Railways decided to increase maximum freight axle load from 20.5 to 25 tons over the next ten to fifteen years at the same time that mechanized track maintenance is being introduced. This is on a large railway system with high capacity utilization which has track materials and components that are not as strong and durable as they should be. The key to successful mechanization on lines which are near capacity, where maintenance today is performed manually between trains, will be the ability of mechanized gangs to obtain a sufficiently high quality of work so that less time is required for track occupancy and maintenance over a period of years. Stronger, more durable materials and track components will be essential. Thus it is planned to lay all major heavy haul trunk lines with 60 kg/m or greater rails by By the end of 1995, 29% of main tracks would be laid with continuous welded rail. Higher-strength concrete crossties and matching higher-capacity elastic fasteners will be introduced. New stone quarries will be opened, and existing quarries either will be reconstructed to provide quality ballast or closed. A track maintenance planning system with new technical standards for track condition management will be implemented. Mr. Mundrey formerly was Adviser Civil Engineering for the Indian Railways Board and is President of M-Consult Engineers of New Delhi, India. Mr. Anderson is Senior Railway Specialist in the Transport Division. This Infrastructure Note is based on a paper they presented o the International Convention of the Austrian Society for Traffic and Transport Science in Linz, Austria, in September TO LEARN MORE Mundrey, J. S Railway Track Engineering, 2nd Ed. New Delhi, India: Tata McGraw-Hill Publishing Company Limited. Federal Railway Administration Track Safety Standards, 49 Code of Federal Regulations Part 213. Washington, D.C.: U.S. Department of Transportation. China Ministry of Railways Present Situation of Chinese Railways and Upgrading Program - Final Report. Beijing, China. Internal report prepared for World Bank Fifth Railway Project.