Construction World June 2016

BEAUTIFUL BRIDGE ABUTMENTS

Hollow core, interlocking precast blocks offer a good looking and cost-effective alternative solution to cast-in-place In the field of retaining walls, engineers are often faced with two choices: specifying a structural yet unattractive wall, or specifying an attractive wall that isn't structural. > private industries and government agencies, for a series of terraces on the inside faces of all four quadrants of the conventional clover leaf interchanges.

abutments, vertical piers, or reinforced concrete grade beams. They are plantable and easy to handle, yet have proven to stand the test of time. Consent LLC, Terraforce Licensee in the United Arab Emirates and GCC region, has been involved in the installation and design of numerous road side Terraforce retaining walls, most notably the erosion control and land- scaping of three large interchanges on the Salwa International Highway. The Salwa highway is the major arterial connection between Saudi Arabia and the coastal capital of Qatar, Doha. All traffic coming into the city of Doha, including from the United Arab Emirates, enters via this route. The QR441-million project allows faster commuting for motorists between Abu Samra and Doha and includes a dual four lane highway with 10 major interchanges, three camel crossing underpasses and twenty two Qatar Petroleum culverts. At Interchanges 15, 17 and 24, a detail was prepared by design engineers of Parsons International Limited, one of the world’s largest engineering and construction consultants for

Their original design, which closely mapped the original ground profiles – a series of tapered and curved embankments running parallel with the edge of the ramps – called for precast walling, but after AG Middle East (AGME), the appointed landscaping contractor, proposed the use of the Terraforce L16 blocks, based on the successful use of the product on Palm Jumeirah island, the alternative designs supplied by Simon Knutton of Knutton Consulting – a well estab- lished engineering consultancy in South Africa – were accepted. The Mirdif interchange, situated at the intersection of Al Khawaneej and Algeria roads in Mirdif, Dubai, was designed by Mirjana Engi- neering and Huesker Synthetics. It replaces an existing crossroads which failed to accommo- date increasing traffic volumes generated by the development of surrounding residential areas. Once the Terraforce design was approved, construction was supervised by joint venture between Aurecon and Al Burj Consultants. The Terraforce blocks proved particu- larity suitable, given the limited space avail- able that required steep side slopes. These were retained with Terraforce L16 (split face) composite retaining walls and vertical Freyssinet panel retaining walls, reducing the impact on surrounding land and facilities. The blocks were used to support both sides of the four ramps, as well as the approaches to the cross road.

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CONSTRUCTION WORLD JUNE 2016