New Pedestrian Bridge in Liège: DYWIDAG Bar Tendons keep 430t Steel Element in Balance
The Belgian city of Liège now has a new, centrally located pedestrian and bicycle bridge that connects the district of Guillemins and the city’s new train station with Park Boverie. The elegant steel suspension bridge with its diagonal hangers is 294m long and crosses the Meuse River with a main span of 163m and a height of approximately 8m. The bridge deck has a wooden cover and is 7m wide.
The two prefabricated main elements of the steel bridge were positioned in only a few days using three floating cranes. For this purpose, the largest element was positioned first and then anchored to the previously prepared foundation blocks using DYWIDAG Bar Post-Tensioning Systems with posterior bond.
The largest, approximately 140m long, 430t main element cantilevered over the river during construction before the gap was closed from the park side by the approximately 60m long, 100t smaller element. To permit a free cantilevering of the main element without any intermediate support, the element was actively stressed against the foundation block using a total of 10, St 835/1,035, 75mm Ø, 4.61m long DYWIDAG-Bar Post-Tensioning Tendons. Afterwards, the DYWIDAG Bar Post-Tensioning System was grouted to achieve corrosion protection.
In all of the other, smaller foundation blocks, St 950/1,050, 18mm - 47mm Ø DYWIDAG Bar Post-Tensioning Systems were successfully installed and stressed. In total, the following DYWIDAG Bar Tendons with a total tonnage of 4.6t were used:
- 12 75 WR, St 835/1,035N/mm², 4.61m long DYWIDAG Bar Tendons,
- 16 47 WR, St 950/1,050N/mm²,
1.475 - 3.26m long DYWIDAG Bar Tendons,
- 7 40 WR, St 950/1,050N/mm²,
1.32 - 1.58m long DYWIDAG Bar Tendons,
- 16 32 WR, St 950/1,050N/mm²,
1.005 - 1.46m long DYWIDAG Bar Tendons,
- 2 26 WR, St 950/1,050N/mm², 0.95m long DYWIDAG Bar Tendons,
- 4 18 WR, St 950/1,050N/mm², 0.95m long DYWIDAG Bar Tendons,
- 4 20mm Ø, S650/800N/mm² INOX Bar Tendons
Thanks to the close cooperation between the Engineer, the General Contractor and DYWIDAG-Systems International, an anchoring solution was found that combined the advantages of high anchoring forces, little required space, low anchor slip and easy installation despite the difficult conditions on site.
The DYWIDAG-Systems International team was available for the General Contractor during installation and assembly of the steel elements in order to be able to react immediately to the respective technical requirements on site.
The complete stressing and corrosion protection work was accompanied by trained stressing engineers. This way, DYWIDAG-Systems International efficiently provided its long-term experience and product know-how to the customer.