1. TUBULAR TRACK
VIEW FROM AUS: COMPLETED FORMATION ( Nominal 3 m width )
SHOWING 1:40 GRADES and 200 m RADIUS
NEW RAILWAY TECHNOLOGY
IN TH E NAMIB DESERT
The Namibian Department of Transport and Consulting Engineers, TUBULAR MODULAR TRACK INSTA L L ATION
Kleber & Associates, have displayed their faith in the Tubular Track ON NORTHWEST ORE LINE
Technology by specifying it for the first 25 km of the railway line
reconstruction between Aus and Luderitz in southern Namibia.
This section comprises steep gradients and sharp curvature, while
extreme temperature variations are also experienced in this portion of
the Namib desert. The main contract was awarded to a fully-fledged
Namibian Company, The Roads Contractor Company Limited, of
Windhoek, Namibia.
The system comprises twin reinforced concrete beams, linked with
steel gauge bars on which rails are continuously supported. As a
ballastless system, it is then laid directly on a specially designed
formation with a 50 to 80 mm grout layer under the beams to fine-tune
vertical alignment. Pre-cast modular sections will be manufactured at
Aus and the laying of the modules will be done by the technology
patent holder, Tubular Track (Pty) Ltd, a South African company. Quote from Spoornet Report BBB5815 dated June 2004:
quot;The Tubular Track(r) modules were designed and tested in the laboratory for 22
Resilience in the system is achieved by the use of rubber-bonded cork ton/axle loading and 5 MGT's per year for a design period of 20 years. The
pads developed by British manufacturer Tiflex and placed continuously results of the laboratory tests and numerical analyses presented in this report, as
between the rails and beams. An interesting aspect of this rail link is well as two other reports that will be referenced herein, indicate that the Tubular
the extensive sand dunes encountered as the line approaches the port Track(r) system, as tested, is a well-engineered alternative to conventional ballast
of Luderitz. The ballastless nature of the Tubular Track system allows track in terms of its technical performance.quot;
it to solve many of the normal problems associated with laying track
on sand, as the fouling of ballast is no longer an issue. Spoornet is respected world-wide for its narrow gauge (1065mm)
railway expertise and for the research and development carried out at
The Tubular Track beam-track railway system, researched and its Track Testing Centre.
developed in South Africa, has been viewed with scepticism by many
conservatives. However, recent tests and results carried out by major The benefits of Tubular Track include the following:
rail authority, Spoornet, the national rail body in South Africa, should do
much to allay these uncertainties. s Lower maintenance costs.
s Reduced rail stresses allow lighter rails to be used.
Laboratory testing and approval of the system was done at the s Vertical and horizontal track geometry remains virtually constant.
Spoornet Track Testing Centre in South Africa, while further in-track s Ballast and tamping costs are eliminated.
main line testing is currently being done between Rustenburg and s No ballast fouling in sandy or bulk-loading environments.
Thabazimbi in north-west South Africa on a line carrying heavy iron ore s No loss of track resilience due to ballast degradation.
and coal traffic. The system has also been in use for some years in s Drainage problems can be easily identified and dealt with.
coal-loading and other sidings, as well as at Metrorail passenger s A narrower formation width is required, generating considerable
platforms with constant rail-to-platform heights. savings on earthworks. e
<#> R A I LWAYS AFRICA