WEB EXCLUSIVE: Saudi Arabia's North South Railway
23 October 2008
Ahead of International Construction's Regional Report on the Middle East in the November edition KHL.com looks at the country's prestigious North-South Railway, an ambitious plan to build a 2200 km-long railway across some of the most inhospitable terrain on the planet.
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Building a 2200 km-long railway is a major undertaking in the kindest of climates - but driving it through the hot Saudi Arabian desert is an added challenge. KHL.com looks at some of the challenges being overcome to deliver this mammoth task.
Saudi Arabia is a country of extremes. Comparable in size to Western Europe, its 5.83 km2 occupy about 80% of the Arabian Peninsula. Not only is it big but it is extremely hot and arid - a peak of 51.7oC being the world's highest ever recorded temperature.
Mostly uninhabited desert with an average rainfall of just 112 mm per year, it is also sitting on 20% of the world's known oil reserves and has valuable deposits of phosphates and Bauxite.
The country has recently embarked on a series of massive infrastructure projects designed to modernise and extend its congested transport links, connecting its major cities and several new ones currently under construction.
Part of its infrastructure expansion includes adding 3200 km of railway to the existing network of 1000 km. The largest part of this scheme is the US$ 2.8 billion North South Rail Project (NSR).
The 818 km-long first phase, known as Phase A, is being constructed by the Al Rashid Trading and Construction Company (RTCC)-Barclay Mowlem-Mitsui joint venture (JV) under a US$ 765 million contract awarded by Public Investment Fund (PIF) of the Saudi Arabian Ministry of Finance.
While Phase A, and B, cover the transportation of minerals - phosphates and Bauxite, Phase C will provide passenger and general freight services between Riyadh and Al Zubairah. Phase D covers an extension to the Jordanian border.
Phase A starts at the Al Jalamid and Al Zubairah mines. It will pass through Al Jawf, Hail, and Al Zubairah, where it will connect to processing facilities at Ras Al Zour. Along the route, RTCC will construct nine bridges, 884 culverts, 22 camel crossings and move an estimated 350 million m3 of sand, rock and earth.
While the US$ 2.8 billion investment may seem huge, the economic rewards are enormous. Phosphate from Al Jalamid will be used to make 3 million tonnes per year of diammonia phosphate fertilizer. Bauxite from Al Zubairah will be refined into alumina and then smelted into aluminium at an adjacent smelter - making it a "mine to metal" operation.
Both the diammonia phosphate and aluminium will then be exported from a new port being built at Ras Al Zour. When finished over 1 billion tonne-km of cargo will be transported each year, reducing the time from mine to port by days.
The Al Jalamid mines contain reserves of 3.1 billion tonnes of phosphates, and the Az Zabirah mines contain reserves of 252 million tonnes of bauxite. Three locomotives and 150 railway cars will transport the ore from the mines to the refinery. Each train will be 3 km long.
Cut and fill
Working on such a mammoth project means breaking it up into manageable chunks. Abdullah A.M. Alkhodari Sons Company (KSC) was awarded the contract to construct 140 km of track across the remote Jawf area, which involves moving 125 million m3 of earth, sand and rock.
"The desert is good for contractors," said Mohammad El Qadi, KSC's equipment manager. "The job is big but the process simple - apart from some scorpions, a few snakes and a lot of sand, there is nothing to get in our way."
‘Simple' is a relative term - over the 140 km stretch that means 75 million m3 of fill and a further 45 million m3 of cut. "We don't need to import any material," says Mr. El-Qadi. "Sand is our raw material and the Cut becomes the Fill."
Essentially a machine project, KSC has invested large sums in buying new equipment, including a fleet of 30 Volvo A35D and A40D articulated haulers. KSC also has a large fleet of Volvo's biggest excavator - the 70 tonne EC700B. The machines have been supplied by Alrehab Equipment & Machinery, Volvo's Saudi Arabian dealer, and are being concentrated on one front - meaning progress is fast.
In the vast desert accuracy is important - the construction is more than laying tracks on the sand. The sand embankments are often 200 m wide at their base and rise at a gradient of 3:1 to a height of up to 70 m.
The loose sand is retained by blocks and compacts down to form a very dense surface. Although the sides of the embankment are steeply raked, the trains that will ultimately run along it will never have to face an incline greater than 1.6°.
Operating costs
The Volvo EC700Bs work 22 hour shifts, as do the 30 haulers. The sand is dense and heavy, and thanks to the fitment of a tailgate, the haulers go fully laden.
"You can't overload the haulers," said Mr. El-Qadi. "The sand is so dry that any excess simply flows over the top of the haul body."
Tyre wear is also good, as the soft sand is not abrasive and running parallel to the rail embankment is a newly built four lane highway that the haulers can use. Haul cycles are typically no more than about 600 m.
However, even in a country where a litre of diesel costs less than US$ 0.10 fuel efficiency is important: KSC brings in five tankers filled with 35000 litres of diesel every day. Added to that, over US$ 1 million is being spent on lubricants, filters and maintenance every month.
Oil testing Landcruisers capable of climbing the steep embankments patrol the site, and over 40 machines have their oil changed every day.
"The 22 hour work days and the high desert temperatures put a big strain on the lubricants," explained Mr. El-Qadi. Part of the thinking behind this is preventative - keeping the machines in peak condition to maximize machine uptime. KSC does the daily maintenance, but defers to Volvo dealer Alrehab for major repairs.
There is still over a year to go before the railway opens in the third quarter of 2009, but already KSC is 15% ahead of schedule. "Much of this progress has been down to machine efficiency," concludes Mr. El-Qadi.
Team player
Also working in the Al-Nafud Desert is Al Farhd Construction Company (AFCC). Its fleet of new machines, bought especially for the project, is entirely supplied by Caterpillar, including Cat 740 articulated dump trucks, D8R and D9R dozers, 631G hauler scrapers, 966H wheeled loaders and 14H graders.
Like KSC the company has found working with the desert sand an interesting proposition. "Apart from the sheer size of the project, the main challenge is the sand, "says Ali Kassem, one of the project's section managers.
"The sand is very fine and very dry and behaves much like cement powder or even water. This means that normal tires on the Cat 740 articulated dump trucks were unable to gain sufficient traction which resulted in the use, by some contractors, of 29.5R25 sand tires," he explained.
There have also been changes to some of the other machines being used, added Mr Kassem. The D8Rs and D9Rs, which are used for cutting and spreading, have all been configured for desert application. So the turbine pre-cleaners and the protection on the radiator cores have prolonged maintenance intervals, for example.
However, such a harsh environment does still cause some problems, particularly on the dozers' undercarriage. To cope with this Cat's dealer, Zahid Tractor, has a team of product support staff keeping a "constant vigil" over the machines via Custom Track Service.
Scheduled oil sampling is also playing a major part in the machine management programme. Samples taken at the remote sites are FedEx-ed to the Zahid Tractor S·O·S laboratory 900 km away in Jeddah.
To date, 8360 samples have been processed from the site and more arrive every day. In addition, the S·O·S teams regularly visit the sites to train the contractors on S·O·S and contamination control.
Haul, and haul again
With so much cut and fill to move, Mr Kassem is conscious of the enormity of the task. "Some of the dune gullies are really huge and even though we're using Cat 740s with their 38-tonne payload, it's an unbelievably huge task. It's like filling a swimming pool using a teaspoon."
Unlike a road, which can include quite severe curves and grades, a railway must be built with much more gentle curves and grades. So typically, three times the amount of earth has to be moved in cut and fill operations.
This becomes even greater when using sand, because the base of embankments, for example, must be twice as wide as those using ordinary earth. "You also need to bring in clay-like earth from far away to cover the embankment and protect it against erosion," said Mr Kassem.
Construction of the railway will see the rails laid on sleepers, which will sit on ballast that will be supported by compacted sub-ballast.
Compaction
Once the earth moving process is complete compaction can then take place. A fleet of 24 Dynapac CA280s, supplied by Dynapac's Saudi Arabian distributor Middle East Development Co (Medco), is compacting the railbed for the entire 818 km.
The CA280, a 14.3 tonne articulated medium heavy vibratory soil compactor, designed to compact all types of base courses and reinforcement courses is equipped with a single 2.13 m-wide drum with a vibration frequency of 33 Hz, which exerts a linear load of 31.9 kg/cm.
The railbed will be laid on an embankment that uses either in situ materials or granite and limestone, excavated at various locations in the desert and trucked to the required section of line, for its construction.
Barclay Mowlem expects to begin work in December on laying the sleepers, which are being manufactured by India's PCM Strescon on site. China is supplying the steel for the rails, and the first shipment of 7500 tonnes arrived in April this year. Progress is anticipated at about 2km a day, with the completion date set for October 2010.
Asaad Arabi, who heads the RTCC side of the consortium, says that there are three types of earthworks required for the railbed.
Mr Arabi said the largest part of the work involves the compaction of granular material found in situ and consisting mainly of sand and granite. A substantial proportion however requires the excavation of granite and limestone from borrow pits, from where the materials are brought to the site and placed between two embankments made from the sand and granite.
A thin layer of sand and granite is then laid over the top of this, and compacted. The third method, which is used infrequently, involves importing sand fill into the sand and granite embankments, and then compacting it.
The CA280s are compacting the fill to a density of 95%. The rollers require three or four passes over the sand and granite fill, and six or seven passes over the imported granite and limestone sections.
Future development
The NSR is expected to start operating in late 2011. "But [this] is only the start of something much bigger," says Awad Shilbayeh, project manager for AFCC.
Zahid Tractor will continue to work on the project's overall objectives by supplying equipment and services to help mine and ship the raw phosphate and bauxite ore. And with such huge reserves of both this promises to be a long-term activity.
