To stay abreast of the growing number of railway projects in Africa, a ballastless track system – Tubular Modular Track – has been created to provide continuous support for rails, using skeletal precast modules in an articulated fixed geometry arrangement, says railway track manufacturer Tubular Track.
The company tells Engineering News that this system competes effectively with the initial cost and installation work rate of conventional ballasted track systems, while providing all the operating cost advantages of other ballastless track systems without the associated logistical complexities during construction.
Engineered in South Africa for African conditions, Tubular Modular Track presents a significant opportunity to boost economic activity, says Tubular Track contract director Craig Tengstrom, adding that “African conditions include intensive working conditions, the need for job creation and skills development, as well as the operation of low-maintenance systems”.
Tubular Modular Track is available for tangent open track, level crossings and turnouts.
Projects in Progress
One of the most recent projects completed by Tubular Track is a third balloon in Ermelo, on the export coal line of South African rail transport company Transnet Freight Rail, on which 70-million tons of coal is transported each year. The project was awarded in October 2012 and is worth R120-million. “While the main contract has been completed, associated smaller works will continue until June 2014,” says Tengstrom.
The work included earthworks consisting of site clearing, the removal of top soil, hard excavation, layer works, roadworks, drainage and drainage structures.
The track work comprised the design and construction of a 2 772 km tubular modular track with a
155 mm radius, which was supplied in 6 m lengths to handle 26 t axle loads.
Six tubular modular turnouts were designed for 1:12 secant turnouts, 11 for 1:12 tangential turnouts and two for 1:9 tangential turnouts.
“Six-metre transition modules were also supplied and installed for a total of 96 m and the project employed 85 people,” says Tengstrom.
Further, Tubular Track Brazil, a subsidiary, was commissioned by Brazilian railway company Ferrovia Centro Atlantica (FCA) to construct a 1.8 km passing loop for 25 t axle load and a 1 000 mm rail gauge on the Tubular Modular Track system used at Estiva Gerbi, in Sao Paulo, Brazil. This passing loop is set to be in operation this month.
“This section of Tubular Modular Track will serve as the new section of the existing line, as it needs to be replaced in due course,” notes Tengstrom.
FCA is concessioned by Brazilian multi-national diversified metals and mining corporation Vale to operate the line.
The line carries about 15 Mt a year, with speeds of 60 km/h and 80 km/h for full and empty trains respectively.
Three-hundred Tubular Modular Track modules, 608 gauge bars, 2 384 stirrups, 3 600 m of resilient pad and 7 200 Pandrol rail fasteners were installed.
“Spare modules and components were sup- plied, equal to 60 m of track. The modules were manufactured near the site in a purpose-fully prepared factory,” says Tengstrom.
“All critical items like moulds, gauge bars and shutters were manufactured in South Africa and shipped to Brazil. “A factory was established in Estiva Gerbi, where 300 modules were produced under full guidance from Tubular Track South Africa,” he adds.
The R16-million project, which started in December 2012, was completed in September, having employed 40 people.
Tubular Track Brazil was also commis-sioned to do the earthworks design, the earthworks construction and the associated drainage, as well as the full installation of the system. Tubular Track South Africa provided full support, as well as on-site skills transfer for the local contractors involved in the project during the installation phase.
The line was set to be commissioned in October 2013.
Meanwhile, in Namibia, Tubular Track South Africa supplied and installed Tubular Modular Track on 74.5 km of main line between Aus and Luderitz, in south-west Namibia, for a 22 t axle load and
1 065 mm gauge for Namibia’s national railway operator, Transnamib.
Phase 2 of the project, which comprises a 50 km rail line, started in October 2012 and is planned for completion by March 2014.
A precast factory was erected for the Transnamib project, from where manufac-turing and installation were undertaken.
“Phase 1 of the project, which consists of 24.5 km, was awarded in March 2004 and completed in November 2006. Phase 1 and Phase 2 are collectively valued at about R200-million. More than 200 people are currently employed at the project,” says Tengstrom.