In one instance, it was required that a section (approximately 1km of double line) of the Metrorail track had to be deviated to accommodate the new Gautrain line. The Client ultimately decided to use Tubular Modular Track for this deviation as it was the most practical solution to the numerous problems that were associated with deviating this section of track.

To begin with, the program for the deviation work was extremely tight and had to dovetail with the bigger Bombardier program which was already in place. Tubular Track was able to submit a suitable program that accelerated the work and met with predetermined mile stones. Secondly, access to the site was limited and by installing Tubular Modular Track (TMT), logistics was simplified by reducing material handling by up to 50% including the elimination of ballast and reducing formation widths. 

Furthermore, the complete deviation is in a cutting. This exacerbates the water problems that was and still is evident in the area. By using TMT, drainage is simplified and once the Gautrain line is complete, the integrated surface drainage, sub-surface and storm water drainage will guarantee designed drainage ensuring expected formation life.

This installation carries a warranty on workmanship as do all of our installations. This in turn offers the Clients piece of mind.

The opportunity to compare Tubular turnouts to conventional (ballasted) turnouts presented itself in this re-modelled yard as 4 Tubular turnouts were installed on the right hand stagger and the left hand stagger was equipped with conventional turnouts. As the turnouts would then be subjected to the same operating conditions and loads, one then can easily determine comparative performance by observing the rate of deterioration for each set. All the sets would be subject to 26 ton axle loads. Annual tonnages vary from 33 MGT to 133 MGT across the turnouts depending on their position in the staggers.

To date, turnout no D17 (insert) has carried in excess of 360 MGT. Maintenance to the turnout since installation has included over lap grinding on only one occasion and the replacement of the resilient pad, between the rail and beam, at 250 MGT.

The local track inspector indicated that the conventional sets required repairs on a three monthly basis while the Tubular sets have only required grinding on one occasion. 

Dr Hannes Grabe, from the University of Pretoria, carried out deflection measurements on both types of turn outs and his results indicated that rail deflections on the Tubular sets are in the order of 60% less than that of the conventional sets. This is very significant in the sense that in terms of fatigue life, a 40kg/m rail on Tubular beams will last longer than a 60kg/m rail on conventional track.

Conclusions after 3 years:

• If the maintenance cycle of the Tubular sets are at least twice as long as that of the conventional sets, then their service life should also be at least twice as long
• The Tubular sets are by far superior in handling longitudinal rail stresses
• The rail-wheel contact stresses are reduced on the Tubular sets
•  The Tubular sets are maintaining their overall geometry much better
• A 40kg/m rail can be used on Tubular Track for low volume heavy haul lines
• No tamping or screening is required for Tubular Track offering further savings

Turnouts at Transnet Freight Rail’s staging yard in Ermelo; With only housekeeping maintenance, these turnouts, on the heavy haul export line to Richards Bay, have seen 450 million gross tons of coal on the line.

IN-MOTION WEIGH BRIDGES

COAL LOADING FACILITIES

GENERAL TRACK

COMMUTER PLATFORMS

TURNOUTS

“You do not touch anything after 10:00 in the morning, especially not any steel items or metal tools. Temperatures of up to 55°C during the day and this, together with severe sandstorms, made it very challenging to complete the project!”

Tubular Track (Pty) Limited, based in Pretoria, South Africa, is a partner in a joint venture company with Central Mining Company Investment Limited (CMCI) named T-Track Saudi. Tubular Track Saudi Arabia in conjunction with the local railway authority recently installed a 900 metre section of Tubular Track on the main railway line between Harad and Al Tawdihiyah in the Eastern Province. This line carries mainly containerised freight between Dammam and the capital, Riyadh.

The project was initiated approximately two years ago with the involve-ment of various role players including government institutions in both countries and private businesses identifying a specific need in Saudi Arabia for providing possible solutions in the form of Tubular Modular Track.

The particular stretch of the main-line where the section is installed, some 40km, operates in some of the harshest conditions due to sand and associated sandstorms. 
Contractors are permanently on standby to clear the line of sand after these storms, to ensure a safe passage for the trains.

Contracts Director for Tubular Track Craig Tengstrom, who recently returned to South Africa after the installation, highlighted some of the severe conditions that were experienced in the desert. “After a couple of weeks in the desert, a person partially acclimatises to the high temperatures; however, the sandstorms are intolerable and depressing”.

The job could not have been done at a worse time of the year – right in the middle of most probably the hottest summer anywhere on the planet. To compound matters, July and August are also the months when the worst sandstorms blow through this region.

“It is extremely depressing to arrive at work the next day, only to find that you must remove tonnes of sand before work can continue. We most probably removed 15,000 tonnes and only replaced 3,000 tonnes. It became difficult to keep morale up at that stage, especially with expat labour who did not understand a word of English. My sign language really improved”, said Craig.

One of the main advantages of using Tubular Track in these desert environments is that there is no ballast that can be fouled causing loss in track resilience which ultimately leads to track failure. Tubular Track on the other hand maintains its resilience in the form of a continuous resilient strip between the modular beam and the rail. Sand cannot penetrate into this rail/beam interface, thereby ensuring continued designed track performance.

Tubular Track has completed the project in Saudi Arabia successfully and is now keenly awaiting the potential of more installations in the current and future expansion of the rail network in the country.

Brief summary of the installation:

• 30 Ton axle loads – freight line
• Standard gauge 1,435mm – 54kg/m rails
• Geotechnical field test to assist in the required layer work design
• Formation and TMT beam design under guidance of Prof Jan Wium (Stellenbosch University) and Dr Herman Wolff (KV3 Consulting)
• Finite Element Analysis produced by Transnet Rail Engineering under guidance of Hannes Maree (Principal Engineer – Track Test Centre)
• Moulds and TMT components were manufactured in South Africa and shipped to Saudi Arabia
• A factory was set up in Dammam were the modules were produced
• Saudi Railways Organisation (SRO – the state railway) transported the modules by rail to the site on flatcars

View more PDF documents from tubulartrack.

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.

Resilience in the system is achieved by the use of rubber-bonded cork pads developed by British manufacturer Tiflex and placed continuously between the rails and beams. An interesting aspect of this rail link is the extensive sand dunes encountered as the line approaches the port of Luderitz. The ballastless nature of the Tubular Track system allows it to solve many of the normal problems associated with laying track on sand, as the fouling of ballast is no longer an issue.

The Tubular Track beam-track railway system, researched and developed in South Africa, has been viewed with scepticism by many conservatives . However, recent tests and results carried out by major rail authority, Spoornet, the national rail body in South Africa, should do much to allay these uncertainties.

Laboratory testing and approval of the system was done at the Spoornet Track Testing Centre in South Africa, while further in-track main line testing is currently being done between Rustenburg and Thabazimbi in north-west South Africa on a line carrying heavy iron ore and coal traffic. The system has also been in use for some years in coal-loading and other sidings, as well as at Metrorail passenger platforms with constant rail-to-platform heights.

Spoornet is respected world-wide for its narrow gauge (1065mm) railway expertise and for the research and development carried out at its Track Testing Centre.

The benefits of Tubular Track include the following:

• Lower maintenance costs
• Reduced rail stresses allow lighter rails to be used
• Vertical and horizontal track geometry remains virtually constant
• Ballast and tamping costs are eliminated
• No ballast fouling in sandy or bulk-loading environments
• No loss of track resilience due to ballast degradation
• Drainage problems can be easily identified and dealt with
• A narrower formation width is required, generating considerable savings on earthworks

Quote from Spoornet Report BBB5815 dated June 2004:
“The Tubular Track(r) modules were designed and tested in the laboratory for 22 ton/axle loading and 5 MGT’s per year for a design period of 20 years. The results of the laboratory tests and numerical analyses presented in this report, as well as two other reports that will be referenced herein, indicate that the Tubular Track system, as tested, is a well-engineered alternative to conventional ballast track in terms of its technical performance. “