Post-Tensioning Tendons installed in Bridges of a Traffic Interchange
The Kallang-Paya Lebar Expressway (KPE) is another project of the Land Transport Authority`s effort to improve the road network in Singapore. Since 2002, when a total of 6 packages of this project were tendered, construction has been underway at full speed. After its scheduled completion in late 2006/early 2007, the 12 km long Kallang-Paya Lebar Expressway will provide a direct link between the new down town area in the South and the housing estates in the North- East of Singapore. The KPE will then also include the longest road tunnel in South- East Asia, since three fourths of that two times three-lane expressway are built underground.
Of the 6 individual contracts, contract 422 is considered by many as one of the most challenging packages as it comprises the construction of a series of underground roadways, slip roads, traffic interchanges and some major surface road widening. One of these traffic interchanges is being built at the intersection of KPE with the Pan Island Expressway (PIE), one of the busiest expressways in Singapore. Three road connections are being built between the new KPE tunnel and the PIE, partly as a bridge across the busy PIE.
Within the scope of contract 422, Utraco Structural Systems Pte. Ltd., DSI`s licensee in Singapore, was awarded a subcontract for the construction of those elevated slip roads with a total length of 2.2 km. That contract also includes the construction of a single span precast bridge over the Pelton canal, the construction of a pedestrian bridge and the supply and installation of pot bearings and expansion joints. Further integral parts of that comprehensive contract are the construction of the pile caps, piers and the superstructure of the elevated slip roads.
The bridges mainly consist of hollow box girders that were cast in place by Utraco Structural Systems Pte. Ltd. A combination of 12- and 19x0.6" DYWIDAG Post- Tensioning Tendons and MA Anchorages were installed into the individual box girders. For the bridge crossing above the PIE, Utraco supplied and installed precast U beams that were reinforced by 6 pcs. 12x0.6" DYWIDAG Tendons.
Using its proprietary USS Formwork and Falsework System, Utraco Structural Systems Pte. Ltd. completed the installation of the in-situ hollow box girders for the bridges during the 3rd quarter of 2005 on schedule.