DYNAMICS OF RAILWAY TRACK SYSTEMS AND THEIR ECONOMIC CONSEQUENCES
British Railways has adopted concrete sleepers and continuous-welded rails as the best means to provide a high performance low annual cost track. Assessing the dynamic loading effect of different axles at different speeds on a less than perfect joint has been done and has produced a very close confirmation between field measurements and a previously calculated formula. Over 50 percent of the rail breaks occur in rails which are not more than ten years old, by which time none have reached the replacement stage due to loss of weight. Maximum bolt-hole stresses occur at the second running-on bolt, but rail-end failures start at the first bolt-hole. The joint consideration of the track and vehicle circumstances has resulted in the design of a three-axle bogie which not only increases the payload by 9 tons for a 2-ton increase in tare weight but reduces the axleload to 13-1/2 tons at an extra cost of less than 2,000 lb. a vehicle. While welded track requires higher installation costs the reduction in day-to-day attention is very marked. Taking 1969 prices, the costs per mile are: (i) long-welded rails on concrete sleepers, 29,000 lb; and (ii) jointed rails timber sleepers, 25,000 lb. But the "equalized" cost per annum is affected by the relative lives and is considerably less for long-welded rails.
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Corporate Authors:
Temple Press Limited
161-166 Fleet Street
Longon EC4, England - Publication Date: 1970-1-2
Media Info
- Features: Figures; Photos; Tables;
- Pagination: p. 19-24
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Serial:
- RAILWAY GAZETTE
- Volume: 126
Subject/Index Terms
- TRT Terms: Axle load force; Concrete; Concrete ties; Construction; Costs; Economics; Maintenance of way; Railroad rails; Railroad ties; Railroad tracks; Railroad traffic; Stresses; Structural design; Technology; Track laying; Velocity; Welded rail; Wheel loads
- Uncontrolled Terms: Track design
- Geographic Terms: United Kingdom
- Old TRIS Terms: Axle loadings; Rail stress; Track construction costs
- Subject Areas: Construction; Economics; Finance; Railroads;
Filing Info
- Accession Number: 00040079
- Record Type: Publication
- Files: TRIS
- Created Date: Jan 22 1976 12:00AM