Saudi Review

In the loop

CONSTRUCTION is gathering pace on Saudi Arabia’s first monorail at King Abdullah Financial District (KAFD) in Riyadh, that will link the financial hub with the city through the Riyadh metro, work on which has just been launched.

The 3.6-km driverless straddle beam monorail system, running in a loop around the district with six stations, will allow workers, visitors and residents easy access to all parts of the area. It will connect into the new Riyadh Metro via a skybridge into the KAFD Metro Station, which will be an interchange for Line One and the terminus of Lines Four and Six.

The company overseeing the development on behalf of the client Riyadh Investment Company (RIC) is French firm Systra, which already has The Palm Jumeirah monorail in Dubai, UAE, to its credit in the Gulf region.

“As the client’s expert adviser on this design-build-operate project, Systra’s role covers every stage: technical specifications, tender process, contract award, design review, construction supervision, testing and commissioning,” says a spokesman for Systra.

Monorail transit systems are new to Saudi Arabia, so RIC – a subsidiary of Public Pension Agency which owns the land – needed an adviser who could help inform every aspect of this project: from defining the system to identifying potential suppliers to managing the constraints and risks.

Systra has been involved in several such projects worldwide, including the Palm monorail. “There are not many firms in the world who have a complete overview of monorail systems, from the initial design right through to supervising the construction works out on site,” explains Olivier Bouhier, Systra project manager. “The practical knowledge and experience gained from supervising the civil works, as we did in Dubai, feeds back into the design process for KAFD.”

The design-build-operate contract for the monorail was awarded to Saudi Oger. Construction of the system began in 2011, with the start of operation expected in 2016.

The construction of the monorail must interface and co-ordinate with the construction of the many buildings in the KAFD and utilities around it.

The monorail system will initially consist of six trains of two cars with a capacity for 3,000 passengers per hour (pph). This capacity can be significantly enhanced in the future by adding more vehicles and reducing the operational headway.

Bombardier Transportation will supply, install, operate and maintain a 3.6-km Innovia Monorail 300 system for the project.

Bombardier has an engineer, procure, construct and operate (EPCO) contract with Saudi Oger for the next-generation system, under which it will design and supply all of the system-wide electrical and mechanical (E&M) elements for the system, including six Innovia trains (12 cars) with Cityflo 650 automatic train control technology for driverless operation as well as providing project management, systems engineering and integration, testing and commissioning.

The modern, wide-bodied, lightweight and aerodynamically styled vehicles will benefit from the latest in vehicle technology. Driverless, the monorail will run on a single elevated guide beam for its entire length, using proven radio-based signalling technology (CBTC). Thanks to the CBTC system, the trains can be operated from the control centre in both normal and reverse mode.

High levels of performance and comfort are a key requirement for the new system, due to the sophistication of the end-users. It will be air-conditioned with onboard security cameras monitored by the control centre during operation.

There will be six elevated stations fully integrated within key attractor buildings, which will be cultural venues aimed to draw people into the district.

The guideway is elevated, with precast concrete beams, pre-stressed and post-tensioned with standard spans of around 30 m and long spans up to 50 m. For safety reasons, and in compliance with the latest safety rules, an aesthetically designed emergency walkway is anchored to the bottom of the beams all along the guideway.

The 16-m-high piers have foundations up to 16 m deep. The foundations are generally located inside five-level underground car parks, which is a challenging constraint.

On this project, Systra has worked for RIC on three distinct contracts: tender preparation and contract award; design review of the systems and of the civil engineering works; and construction supervision, installation, testing and commissioning.

“In drawing up the tender documents, Systra had to review the existing KAFD transport masterplan with the provision for the monorail; review the feasibility study; create a concept design; and prepare performance and functional specifications. Systra was also responsible for the prequalification of monorail contractors, analysing four bids, both technically and commercially, assisting in negotiations and advising on contract award,” says Bouhier.

The design review contract requires Systra to check both the civil work design and the systems design. Systra must oversee all aspects of the construction site, including the manufacture of the concrete viaduct elements in a dedicated precasting yard; and also work in the manufacturers’ factories to verify tests on equipment including signalling, the control centre system, telecommunications, track switches and rolling stock.

Bouhier says the main challenge on this project is managing the very complex environment: more than 30 buildings, car-parks, roads, tunnels and utilities are under construction at the same time and in the same areas as the monorail. Systra is involved on a daily basis, dealing with interface coordination and resolving site challenges.

“These are key issues for the project in avoiding delay,” says Bouhier. “We take a very proactive approach in order to find solutions which give the best possible result for the client and which bring the least impact to the contractor.”

Systra’s expertise in civil work and monorail systems specifically, helps with the resolution of day-to-day issues. Its role will continue through testing and commissioning, right until the monorail starts operation.