Construction of the Esplanade Riel Pedestrian Bridge to Connect Communities

Context

The city of Winnipeg planned the construction of a new bridge across the Red River in order to connect both culturally and economically these historically English and French quarters. For this reason a public project committee was established that reflected the diversity of the inhabitants directly affected by the bridge. This committee played an important role in the early design selection for the bridge.

This led to the construction of two bridges - the Provencher Paired Bridges: A four-lane bridge for cars and trucks and a smaller, more elegant bridge to be exclusively used by pedestrians, cyclists and recreational users. Some of the unique features of the pedestrian bridge, the Esplanade Riel, include an architectural composite tower that is prestressed with a cantilevered and stayed semi-circular plaza area at the base of the tower, which provides space for commercial activities and also accommodates a restaurant. This "annex" to a bridge is absolutely new for bridges in North America.

From an engineers point of view, this highly challenging stay-cable pedestrian bridge reflects the lightness of its use as a pedestrian bridge by incorporating a slightly inclined, elegant tapered pylon. The 7 m wide bridge deck has spans of 110 m and 87 m. The top of the pylon is 57 m above the bridge deck, which, in turn, is about 11 m above the water level.

Solution

The single reinforced concrete tower which is inclined from the stay plane is founded on a pile cap footing and eleven Ø 1.83 m bored piles. It was erected using 10 m long precast reinforced concrete elements. These precast elements were subsequently post-tensioned with DYWIDAG Post-Tensioning Systems. The plaza area and the shorter west span were built on a falsework. The longer east span was built using the free cantilever construction method and a form traveller supplied, erected and operated by DYWIDAG. Based on a proposal submitted by the engineers from DYWIDAG and Buckland & Taylor, the DYNA Grip® Stay Cables were used for the temporary support of the DYWIDAG Form Traveller.

Precast reinforced concrete elements were used for anchoring the stay cables in the bridge deck; thus eliminating the need to adjust the formwork and the form traveller to the varying angles of the cables. These alternatives were decisive for the awarding of the contract and saved the city of Winnipeg CAN$2.0 million over the originally planned bridge option designed to be built using precast elements. The stay cables were spaced 10 m apart. This spacing makes it possible to replace individual cables without the need to install falsework. For additional reinforcement the super structure of the entire bridge was also internally post-tensioned in the longitudinal direction using DYWIDAG Tendons supplied and installed by DYWIDAG.

The 44 type DG-P12 and DG-P14 DYNA Grip® Stay Cables consist of galvanized and waxed strands, encased in a 1.5 mm thick extruded HDPE sheathing. The outer diameter of the stay cables is 125 mm or 140 mm with 8.0 mm wall thickness of HDPE sheathing. The lengths of the stay cables that also anchor the plaza vary from 37.5 m to 107.1 m. They are connected to the pylon at the upper anchorage. Installation of the DYNA Grip® Stay Cables took place between temperatures of -35°C and +30°C.

DYWIDAG is proud to have contributed to the successful construction of the new Esplanade Riel in a record breaking construction time through innovative alternative proposals and through the supply of high quality products. The Vancouver Regional Construction Association in Canada honoured DYWIDAG with the Award of Excellence 2004 in the category Trade Contractor for its achievements in this project.

The bridge was opened in summer 2004.