6.6 C
Monday, May 27, 2024

New rails in the desert

Listen to this article

Saudi Arabia and the UAE. This plan is being co-ordinated by the Arab Gulf Co-operation Council (GCC) whose member states are Bahrain, Saudi Arabia, Oman, Qatar, Kuwait and the UAE.

In 2009, Federal Law No 2 provided the mandate to construct and operate a 1200 kilometre long railway network within the UAE at a cost of £7.4 billion. This was originally named the ‘Union Railway’, but it was re-launched in 2011 as ‘Etihad Rail’ with a new logo which incorporates the colours of the UAE flag.

Etihad Rail’s memoranda of understanding with 14 companies in the chemical, logistics and agriculture sectors show the potential demand for rail freight within the UAE. Once the network is complete, it is expected to carry 50 million tonnes and 16 million passengers each year.

Three stage programme

Construction is being undertaken in three stages. The first is a 264km freight line from the port of Ruwais. This line runs along the coast for 117km and heads inland for 20km to the Habshan gas field. From there, it goes further inland for a further 144km to the Shah gas field. Its construction requires 10 underbridges, 29 overbridges, 12 pipeline crossings and 30 culverts. The bridges include significant structures crossing major coastal highways.

With construction almost complete, the first trains are planned to run from Habshan late in 2013 and from Shah in 2014. Trains will transport up to 22,000 tonnes of sulphur per day from these oil fields to Ruwais. Sulphur is a valuable by-product from oil extraction and is currently transported in liquid form by approximately 300 lorry movements per day. New plants will produce granulated sulphur for transportation by train.

Things moved quickly after Federal Law No 2 was passed. Atkins was appointed as preliminary engineering consultant to undertake outline design and a joint venture of Parsons and AECOM was appointed as project managers in 2010. The following year, the construction contract for stage one was awarded to a consortium of the Italian firms Saipem and Tecnimont together with UAE-based Dodsal Engineering. This was a design and construction contract for the civil engineering, communication systems and the construction of a depot.

In January 2012, the consortium appointed Ansaldo to supply communication and signalling systems to ETCS level 2. PCM Strescon Overseas Ventures is manufacturing the estimated 540,000 sleepers required in a brand new factory. The Indian company has already Track laying train [online]set up two factories in Saudi Arabia, with the world’s highest production capacities, to supply 2.6 million sleepers to the Saudi Arabian Railways (SAR) North-South Railway Project.

Stage two, planned to be completed by 2017, is 628km long and extends phase one in both directions to the Saudi Arabian and Oman borders with the addition of a new line to Dubai’s Jebel Ali Port. The remainder of the mixed‐traffic network in the Emirate of Abu Dhabi and the connection to Jebel Ali Port is safeguarded and preliminary engineering for this stage is complete. Tendering is in progress.

The final stage of the project, due to be opened in 2018, will cover 279km to the northern emirates and the strategically important port of Fujairah. Here, ships can be loaded and unloaded without having to pass through the straits of Hormuz. Etihad Rail is working closely with each of the Emirates involved to define and safeguard the route. Preliminary engineering is well underway.

The new railway

In a country with no mainline railways, one of the challenges of constructing and operating a new network is the requirement for a new rail legislative framework and a set of standards and rules. Etihad Rail is working closely with the UAE government to advise on the legislation required and is developing the necessary management systems as it is developed. Etihad Rail will have to ensure compliance with these systems once the railway is operational as it is both the developer and operator of the railway, working with leading industry partners to ensure it uses the best available technology and management practices.

Engineering standards are essentially UIC above the axle box and a mix of American and Australian standards below as the new railway is primarily heavy haul. Operating standards will be based on UK practice.

The new railway network will be a mainly double track 1200km standard-gauge network controlled by in-cab signalling to ETCS level 2 with GSM-R radio. The twin tracks will typically require a 20.3 metre corridor to accommodate a walkway, cable routes, passive provision for catenary masts and an access track. Structural clearances will be provided for double-stacked containers and possible future electrification. It will be a mixed-traffic network with long passing loops. Freight trains with axle loads up to 32 tonnes will operate at 120km/ hour and passenger trains at 200km/hr.

Challenging terrain

Building and operating a railway across the desert’s shifting sands has its challenges. There are three basic types of terrain, each with its own issues. By the coast is sabkha, mostly flat land with a salt crust just above the water table (about a metre below the surface) which is very aggressive towards construction materials. Below the salt crust are unconsolidated silica and carbonate sands around 10 metres deep.

A little further inland is a low- amplitude high-frequency dunes system. These dunes are mobile with loose surface sand. Beyond these are high-amplitude low- frequency dunes, typically 80 to 150 metres high with loose sand and an inter-dune surface crust.

As a result, special consolidation techniques are being used for the track bed together with an estimated 15 million cubic metres of fill material. Geomorphologic studies were undertaken to understand the behaviour of the sand dunes and the wind deposition of sand.

These studies identified those areas most likely to be affected adversely and were used to determine the optimum track alignment through the desert. They also were used to specify where mitigation measures such as berms (raised banks) and wind monitoring stations were required.

In operation, sand contamination of ballast will be controlled by specialist on-track plant with sand vacuums and monitored by ground penetrating radar. Derailment and operational disruption caused by sand is a major ongoing concern and Etihad Rail has looked at the way Saudi Arabian Railways deals with sand to determine the best way to mitigate sand problems.

Desert construction

Construction in the desert presents significant health and safety issues with heat stress being a major concern, particularly during the extreme temperatures of the summer months. Driving is also a significant risk given the dust, the large concentration of construction traffic and the distances involved. Many of the workforce have never worked on railways and, as a result, much time has been spent on training, including the risk of train operations. Etihad Rail has already attained 9 million lost-time accident-free hours worked, which is a significant achievement for a project of this scale.

Environmental measures specific to desert railway construction include a dewatered management plan to protect groundwater in coastal areas and protection of the desert eco-system. This includes avoidance of work at night (an active time for desert wildlife), relocating species outside construction zones and the construction of animal crossings. For phase one this includes 10 camel, 22 gazelle and 78 reptile underpasses.

Rolling Stock

Etihad Rail anticipates that its network will eventually require 100 locomotives and 5000 freight wagons. For stage one, seven locomotives and 240 covered hoppers will provide one train a day from both the Shah and Habshan oil fields, each consisting of three locomotives hauling up to 110 wagons carrying 11,000 tonnes of granulated sulphur.

The locomotives are 3,400kW SD70ACSAerial View of Al Mirfa site. [online] models designed and manufactured by Electro-Motive Diesel of North America. These have AC traction motors and are custom-built for desert conditions with pulse filtration and ventilation systems to control fine blown sand. Similar locomotives are already in use on Saudi Arabian Railways.

The 100-tonne capacity wagons for phase one are top loading / bottom discharge with sealed hatches. They are supplied by the China South Locomotive and Rolling Stock Corporation Limited (CSR). The first of these wagons arrived in the UAE in December last year.

World records

The UAE’s rapid economic development has resulted in various world records. Etihad is the fastest growing airline in the history of commercial aviation; the Dubai metro is the world’s longest fully-automated passenger metro system; the Burj Khalifa Tower is the world’s tallest building and the Burj Al Arab is the world’s first 7-star hotel. Yet, up to now, the UAE is one of few countries without a heavy rail network.

Scheduled for completion in 2018, the new network will provide additional stimulus to the country’s economy. Etihad Rail considers that “once complete, the railway will redefine logistics and transport in the regions to support the government’s mission to build a diversified economy”. It will be interesting to see if its railway will give the UAE any more world records.


Please enter your comment!
Please enter your name here

Latest Rail News

Stadler has built half of the new Tyne and Wear Metro fleet

The project to manufacture and supply new trains for the Tyne and Wear Metro has reached a critical milestone,...

More like this...