Installation of the Walterdale Bridge, Canada
ALE has successfully completed the installation of the arches in the Walterdale Bridge in the city of Edmonton, the capital of Alberta, in Canada.
ALE was contracted by APJV (ACCIONA – Pacer joint venture) to proceed with the skidding, navigation and heavy lifting of the main arch.
ALE performed the load transfer to the barges, carefully controlling the load transfer and level using the monitored external ballasting system for modular pontoons. Designed by ALE, this enables work in 18 separate tanks without physical access to them. The skidding was performed by coordinating the skid system located on land with the mooring system located on the barges. The mooring system was composed of four winches attached to the barge.
Once the skidding was complete, the first barge was relocated and a second one modular barge was introduced in such way that the arch was ready to navigate onto both pontoons now located on the interior supports. The pontoons were navigated on the North Saskatchewan River until they reached the final position. ALE used the mooring system installed on board and changed the different berths on land, according to the sequence accurately defined and calculated in the method statement.
Once the 1,000t central arch was positioned ready for in vertical lifting, it was supported again onto the skid shoes located on the foundation of the tower using the ballasting system until the weight was transferred from the barges.
Because of the river’s limited water depth in Autumn, ALE could only navigate during the winter season. Despite the narrow timeframe and frosty weather conditions, ALE’s rigorous preparation of the manoeuvres, coupled with engineering modifications to reduce the arch dimensions, enabled the safe and timely navigation.
ALE then performed the first lift two months later in temperatures of -20° and three months the second and final lift of the 1,800t main arch was executed. The main arch, measuring 146m long, was lifted 20m high using four 850t lifting strand jacks and four auxiliary lifting towers. Two 850t bow string strand jacks were pulled to produce the arch.
The final phase of the erection of the arch involved the adjustment and welding of the main arch by the client.
The replacement project, with a budget of $155 million, was the first to install this type of bridge in the city of Edmonton. This modern structure, with two arches measuring 56m high, will replace the old Walterdale Bridge, which has served the city for over a century.