Bridges & Footbridges

Great architectural freedom for the pedestrian walkways at Papatoetoe in New Zealand

The first pedestrian walkway in the public transport station redeployment programme in Auckland province measures 175 metres long with a 20-metre span for an impressive display of lightness and fluidity. Built to service the Papatoetoe station platforms, this walkway is a prime example of all the innovative qualities of Ductal®.
The lightness combined with the solidity of this new concrete provides greater architectural freedom as exemplified by very wide spans resting on only two prefabricated segments that also support the walkway roof.
A fluidity that is reinforced by large perforations that lighten the overall structure while providing it with a very original identity and aesthetic.

The pedestrian bridge in Seonyu, also called the Bridge of Peace, was inaugurated in April 2002. It crosses the Han River, linking Sunyudo Island (a natural park) to the heart of the South Korean capital. This footbridge, designed by French architect Rudy Ricciotti, features an elegant, ultra-high performance concrete central arch 120 meters long and 4.3 meters wide. It is extremely thin, like a sail billowing between the two banks of land. This challenging artistic feat and technical prowess was made possible with Ductal®, which provided extreme fluidity to the lines of the deck where thickness does not exceed 3 cm. Ductal® enables such technical daring due to its superior compressive and flexural strengths and outstanding ductility.

The Sakata Mirai footbridge was built to replace the former concrete bridge which has spanned the Niita River, in the Town of Sakata, for 40 years. Ductal®, used for the first time in Japan to build the new footbridge, enabled creation of one single span; 50 meters long and 2.4 meters wide. The deck is built of perforated precast elements to give the bridge better deformation resistance and less exposure to the wind.

Chryso, producer of admixtures and additives for the construction industry, in Sermaises (Loiret), built a 19-meter long, 1.6-meter wide walkway, entirely in Ductal®, for one of its warehouses. The footbridge, built of three precast elements with no reinforcement, sits on steel pillars, 3-meter high, which are independent of the surrounding structure. Ductal® replaced the original design which called for steel and wood, offering six times greater load resistance than required standards, with a deck that is only 8 cm thick. The Ductal® solution also provided outstanding fire resistance required for a storage warehouse that contains large quantities of chemical products.

The pedestrian/bicycle bridge in Sherbrooke, Quebec (Canada), which crosses the Magog River, provided opportunity for early experimental use of Ductal® in 1997; and showcased the material’s true technical prowess. The use of Ductal® enabled construction of a single 60-meter long span only 3 cm thick, paving the way for the later use of Ductal® in long-span roofing. Three major technological innovations were realized with this project – the total absence of steel bar reinforcement, enabling the creation of thin, elegant structures (and enhancing urban landscape), use of small prestressed elements, and confinement of web member diagonals in stainless steel tubes.

The Yokemuri footbridge, completed in January 2004, is located in the Yamagata region of Japan. The footbridge is built using the principle of a square box girder frame of 35.3 meters length, 3.5 meters width, and 0.95 meters height. The construction was conducted by Taisei with Ductal® premix, produced and supplied by Taiheiyo Cement Corporation. Ductal®’s durability properties are used to withstand the severe climatic environments in that region (high differences of temperatures).

The first road bridge made of Ductal®, “Shepherds Bridge”, has been erected 150 km north of Sydney (Australia), to replace an old, obsolete timber bridge. It measures 15 meters long by 21 meters wide. In terms of structures, 16 girders made of Ductal®, support a reinforced concrete slab, cast in-place over thin plates of Ductal® used as formwork and set over the girders. This bridge was designed and built by VSL-Australia, for the Australian RTA (Roads and Traffic Authority), to provide durability, strength and a reduced maintenance cost.

The US Federal Highway Administration (FHWA) has launched a comprehensive study to design solutions based on high performance materials with a goal to significantly reduce the number of obsolete bridges over a couple of decades. From the initial results of several material testings, Ductal® has proven to be the best solution, providing reduced maintenance costs and improved durability. Consequently, a decision was made to erect an experimental bridge at FHWA’s testing facilities in McLean, Virginia (near Washington, DC). This optimized bridge is made of two pi shaped girders; 21.3 meters long by 2.44 meters wide, with pretention strands. The design of these girders was optimized through an in-depth study conducted by M.I.T. (Massachusetts Institute of Technology).